Enemy-Detecting Radar

Oh... good...it works.

"I also invented your radar, which somehow knows which direction enemy soldiers are looking and even when they yawn."

— Mei Ling, ToastyFrog.com Thumbnail Theater: "Metal Gear Solid, Part 1"

A few real-life combat vehicles have radar support (and all seafaring vessels are required to have at least one) that can help the pilot navigate the battlefield and avoid enemies, so it's no surprise that this is often part of video games that feature such systems. Sometimes it's justified as your character's equipment, or psychic, abilities or Handwaved as A Wizard Did It; other times it's just there with no explanation except to make the player's life easier. It may also partially model non-visual cues that humans tend to get like positional sound location (an aspect of the cocktail party effect) which are difficult to implement in video game sound systems which often lack the ability to create true positional sound. Alternately, the "radar" is used to detect hidden items instead.

In some games, you will encounter enemies who can interfere with your radar in some way or other. Some jam the radar, filling the screen with static, others just don't show up at all or only show up randomly for a split second. This is usually justified with stealth technology and almost never affects visual detection or lock-ons.

In cases where both enemy and friendly units will be shown, they will be color-coded]] for the player's convenience.

A common variation is for the radar to only display enemy units that are attacking. It's also often tied to Fog of War, showing only enemies that you actually see normally.

It may be part of a Level-Map Display.

Related to Detect Evil, Aura Vision and Enemy Scan.

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Video Game Examples

Action Adventure

• Detective Mode in Batman: Arkham Asylum and its sequels lets you see the glowing X-ray skeletons of people through walls; during sneaking sections this is vital. In a few cases this can be used to spoil the surprise of an inmate hiding in a box to ambush you.

• In Ecco the Dolphin, using your echolocation tells you where enemies are.
• The Compass in The Legend of Zelda only pointed out the location of the boss and item boxes (starting from The Legend of Zelda: Link's Awakening); since the 3-D titles it also shows the direction you are facing.
• Metroid:
  • In Metroid: Samus Returns, the Metroid counter from the original Metroid II: Return of Samus gets a slight upgrade; it now blinks whenever a Metroid is close. The closer the Metroid, the darker the color of the icon and the more quickly it blinks. The Metroid amiibo takes this further by marking the nearest Metroid on your map screen.
  • In Metroid Dread, the game's mini-map shows an E.M.M.I.'s location whenever Samus enters its zone. Though only when the E.M.M.I. is in close proximity.

• Project Eden has a radar that beeps when enemies are near, which can get a little annoying when there is a nearby enemy you can't reach.
• RemiLore: Lost Girl in the Lands of Lore: When an enemy is off-screen for long enough, an arrow will appear near Remi to point to its location.
• Since Spider-Man has a Spider-Sense that alerts him to danger, games featuring him sometimes have it as part of the gameplay, though how it is integrated can vary greatly.
• The minimap in Syndicate shows the position of people, and distinguishes between civilians, police, enemy agents and targets. This is often known as an IFF (Identify Friend/Foe) system. They exist in Real Life, but those can only tell you if a signal is coming from a known friendly or not. It can't distinguish between enemies, civilians, or allies whose codes haven't been registered as such.

Eastern RPG

• The 7th Saga gives you a crystal ball that allows you to detect enemies, among other things. This functionality seems present mostly for the game to taunt you, as it's nearly impossible to avoid running into them.
• The Dark Cloud games feature a "Magic Crystal" on each dungeon floor which will reveal the locations of any remaining enemies and treasure chests.

• In Final Fantasy XII, a mini-map is shown at all times in the corner of the screen. Green dots are NPCs, blue dots are either your allies or a neutral character in the battlefield, red dots are foes, and huge red dots are bosses.
• The Monster Hunter series has the Paintball item, which allows a hunter to see where their mark is located on the onscreen map.
• A function of the mini-map in Odin Sphere is to show enemy locations and even any projectiles they may be firing.
• Parasite Eve 2 has a radar system that shows how close enemies are to you, but only if you have the GPS item equipped or are wearing armor that has a GPS built in.
• Persona 3 has a radar screen that shows enemies, treasures, and general geography while exploring Tartarus. In one section, the enemies tend to blend into the dark background and the radar becomes that much more useful.
• Pokémon:
  • Over time, the "Item Finder" has evolved from a somewhat unhelpful noise maker if you were within 50 yards of something, to a "DowsingMCHN" that points out the EXACT location of a hidden item. It wasn't until Fire Red and Leaf Green that players got access to the "Vs. Seeker," which could detect trainers. That is, those who wanted to battle or have a rematch and were onscreen.
  • The Pokeradar in Gen IV points you to hidden Pokemon via shaking grass. Trouble is it lasts a few steps and then needs 50 steps to recharge.
  • Pokémon Legends: Arceus has a rudimentary one that alerts you with an icon near the top of the screen, a horizontal red line with an eye in the middle, if any wild Pokémon are attempting to attack you and you're not in battle with them. The music also changes; which one it uses depends on how safe you are if you are to an attack from the wild Pokémon.
• The Star Ocean games have a radar when battling the enemy to show the relative positions of your team and the enemy's.
• Valkyria Chronicles: The overworld map shows the position of all allies and visible enemies.
• Valkyrie Profile 2: Silmeria has a radar when battling the enemy to show the relative positions of your team and the enemy's, as well as each enemy's range of attack when zoomed in. The field map also shows the location of enemies, and changes their color depending on whether they're active (red), defeated (grey), or frozen in place by Alicia's photons (purple).
• Wild ARMs 2 has a hidden item radar.

First-Person Shooter

• In Aliens: Colonial Marines, the motion tracker's a bulky machine you cannot have equipped at the same time as a gun. It also has a proxemity function, the distinctive, hot-and-cold "mlinging... mlinging... mlinging..." audio clue from the film to let you know how close an enemy is.
• In Aliens vs. Predator (2010), the motion tracker appears as a HUD element (and yes, it keeps the proximity warning audio cues).

• Vehicles and the spacesuit in both Battle Zone 1998 and its sequel have a circular radar display, which shows the terrain in 3-dimensional wireframe, with friendly and enemy contacts displayed on top of the wireframe terrain. Different vehicles have different radar ranges, radar pulse rates, and inherent stealth abilities, the latter of which can be augmented by the RED Field generator or the Scion's Jammer building, which completely hides a vehicle from radar.
• The Call of Duty series plays with this. In just about every game, there's a map in the top left corner of the screen which shows your squadmates as green chevrons and red dots representing enemy fire, in both World War II and Modern settings. This map could be disabled or enhanced in many ways:
  • Calling a UAV or Recon Plane (depending on the setting) will periodically give you all enemy positions every few seconds. Oddly enough, even if said enemies are inside concrete bunkers with no windows. Modern Warfare 3 includes an "Advanced UAV" that updates more often, while the Black Ops games include, respectively, an SR-71 Blackbird, an "Orbital VSAT", and a "High Altitude Telemetry Reconnaissance" vehicle that show the positions of enemies in real-time (marking them as red chevrons) and, except for the H.A.T.R., can't be shot down like the standard UAV.
  • Using tools/perks like UAV Jammer, Camouflage, Cold Blooded, Ghost, Assassin, Off the Grid, Low Profile or even simply shooting the UAV down will hide you from this sort of detection.
  • As well, these maps can be defeated by using suppressed weapons; firing one wouldn't have you show up on enemy radar.
  • In Modern Warfare 2, a Counter-UAV will completely disable enemy radar; it replaces the map, friendly positions, and enemy positions with static.
  • The Scrambler perk also makes enemy radar more static-filled the closer to enemy personnel you get. Unfortunately, this can also act as an early-warning system to said enemies.
  • Modern Warfare 2 and 3 also have heartbeat sensors available for certain weapons; and these can, for some reason, distinguish between friendly and enemy heartbeats. However, these can also be defeated by the 'Ninja' perk, which makes you invisible to such sensors.
  • Finally, all enemy electronics can be disabled by using an EMP, which makes the only method of detection the Mark One Eyeball. Oddly enough, this only affects the enemy team - not yours. This is, however, averted in Hardcore mode where an EMP will disable all electronics.
• Catacomb Abyss and its sequels have you collect crystals throughout the game; each crystal allows you to see one specific type of enemy on your crystal ball (like a radar, it shows enemies at some distance all around you, though it isn't an automap)
• Command & Conquer: Renegade had a radar that shows the position of enemies, and is jammed by enemy communications centers. In multiplayer mode, it only shows allies (in the default settings, anyway).

• Deadhunt grants you a circular radar on the lower-left corner. Which is neat, because your only way to progress to the next stage is by killing everything on the map.
• In Deus Ex: Human Revolution, your cybernetically augmented vision includes a radar in bottom-left corner that shows locations of friendlies (as green triangles), hostiles (as grey triangles that turn yellow when alerted and red when attacking) and cameras. It can be upgraded to also show the enemies' field of vision and even how long they will remain alerted.
• The top-down automaps in Doom and Doom II allow you to see enemies (and other objects) with the proper cheat codes on.
• In Far Cry the player character finds a set of binoculars near the beginning of the game which allows him to isolate the tracking beacons of targetted enemies, putting them on the radar. So, once the enemies have been spotted once, they show up on the radar. This returns in Far Cry 3 and all later games in the series, by way of marking enemies through your camera or use of a craftable syringe which highlights enemies.
• Genetic Species gives you a translucent grey map on the upper-corner of the screen that shows you the next path and where enemies may be hiding to ambush you.

• In Guns of Icarus, the radar is absolutely vital for tracking the position of enemies, since your vision will be obscured by clouds and weather conditions, and you'll be attacked from all sides—enemies will retreat out of your vision range and circle around to the other side of your ship—so if you don't watch the radar, expect to die.
• Halo puts a radar on the player's HUD in both single-player and multiplayer modes that displays the hostiles' locations. The one in Halo 4 can even indicate vehicle type (e.g. if an enemy is driving a Wraith, they'll appear in the shape of a Wraith on your motion tracker). That said, the tracker can be foiled by either crouch-walking or just moving really slowly.
• Krazy Ivan gives you one on your screen, next to where the weapons indicator is at. Justified since you're piloting a giant robot, which have it's own built-in radar system.
• MAG has different uniforms for different factions, but allied players always show up as blue on the minimap and enemy players show up as red. This has led to expressions like "hey blue dot, heal me" and "fighting some red dot when..."
• Marathon features the motion tracker on which humans and defense drones appear as green squares, aliens as red triangles, and hostile players during net play as yellow squares.

• The HUD minimap in Nitemare 3D has an optional overlay that shows enemies in red.
• In No One Lives Forever, your radar doesn't show nearby enemies... unless you shoot them with a "tracking dart" (which takes some skill), after which they appear as red dots on it.

• In PlanetSide 2, your map will report the position of enemies firing non-silenced weapons. Spotting an enemy tags them on radar, allowing all your allies to see real-time aim and position tracking on their map for a few seconds. Devices like Scout Radar on vehicles, and the infiltrator's Motion Spotter and Recon Darts allow you to expand radar capability.

• Red Faction: Guerilla has an in-built radar that shows enemy vehicles. You can purchase an upgrade later on that allows you to see the location of enemy soldiers, too.
• Sensory Overload has the hidden Radar Display Chip, along with the Proximity Detector which beeps when enemies are nearby, and the Trap Detector which shows trap triggers on the radar. One of the McNinja enemies has an Invisibility Cloak that also prevents radar detection.
• S.T.A.L.K.E.R.'s HUD is partly related to the lead character's PDA, which includes a map that marks the locations of other PDA-users and identifies whether they are friendly, hostile, or dead. However, enemies can "cloak" themselves, only appearing on the map when you can see them.

• Terminator Rampage grants you a mini-screen on the bottom right that provides an overhead layout of the level you're currently in, and registers enemies as dots. It even briefly turns into a picture of the enemy if you're under attack.
• TimeShift: Your radar can detect enemies (Red), allies (Green) and usable vehicles (Yellow). It also helpfully tells you if they are above, below or on the same level as you.

Hack And Slash

• No More Heroes requires you to earn the "Memory of White", a minimap with the enemies in purple and the treasures in yellow, by collecting Lovikov balls. No More Heroes 2: Desperate Struggle averts the Bag of Spilling by letting Travis keep it.
• All of the Warriors series (Dynasty Warriors, Samurai Warriors, Warriors Orochi, the Gundam spinoff) has an overworld map that colors allied units blue, enemies red, and other factions yellow.

MMORPG

• Final Fantasy XI possesses two radar systems. The first can be used by all the classes in the game and is part of the normal HUD, but actual targets you can attack will only show up if you have the Beastmaster, Ninja, Thief, Ranger, Summoner, or Blue Mage jobs either as your main or subjob. Beastmasters and Rangers(and anyone who subs them) can use Wide Scan, which essentially uses the map of the area as a radar for NPCs and monsters. You can even select one to "track", which allows you to hunt it down by pointing towards it on the normal radar.
• Kingdom of Loathing has a radar function in the Meteoid subgame. It doesn't begin detecting enemies until it's been upgraded, though.
• The Divine Herald from Nexus Clash can detect when there are demons in the area. The Herald can only find out how many demons are nearby this way and not quite exactly where they are, and it may take a few pings of the radar to triangulate the location of their target.
• World of Warcraft:
  • The Hunter class has a feature that allows you to see all of one type of mob within the range of your minimap.
  • This was previously limited to only tracking one type of thing at a time, which was fairly useless if the Hunter was also a miner and didn't want to miss out on collecting shiny rocks. Currently, the number of things that can be simultaneously tracked is limited only by the player's ability to sort through all of the dots.
  • Paladins can track undead, warlocks can track demons, and druids in cat form can track humanoids.
    • And herbalists can track plants, and miners can track rocks....
    • And rogues can track treasure chests.

Real-Time Strategy

• In the side-scrolling Real-Time Strategy Armor Alley, your radar displays everything on the length of the battlefield...unless your Hero Unit strays near an enemy signal-jamming van, which will cause the radar display to flicker blank.
• In Company of Heroes, the British can choose the Royal Commandos Commander Tree (the Brits actually invented Radar in real WW2). You'll receive 3 Radar positions, which you can place randomly on the quadrangular map. This forms a triange between the three stations (see Bermuda Triangle), a Fog of War-free zone, where you can spot any enemy movments. This method can only supervise up to 50% of the map though (a triangle may fit twice into a quadrangle!), so you better concentrate all your scouts on the other halve...
• Command & Conquer:
  • In the original games, you don't have a minimap unless you build a Radar Dome, which will then show off the entire map (though areas covered by the shroud would appear as black space). Additionally, the later games add ways of detecting stealth units (typically, light vehicles might have sensors which reveal their location, meaning that players would be well advised to keep a few stealth detecting units around to avoid being ambushed).
  • Though there were a few missions in the series that gave you the minimap even without a Communications Center (though those missions usually were the ones before you could build a Comm. Center, or those with no base at all).
  • Command & Conquer: Generals: The USA can use a satellite scan (and have radar access) right off the bat as long as they have Command Centers, an ability that can eventually be researched by the GLA for their Radar Vans. The Chinese don't get it, instead having to rely on the detection capabilities of their troop crawlers.
• Dune II had the Outpost building, which gives you a radar screen that tracks your enemies (including sand worms).
• The real-time strategy/real-time combat hybrid Final Legacy has a radar that shows only several ships at once (the ones that can currently be fought), and all currently discovered enemy missile launchers. If the enemy launches missiles from not-yet-discovered launchers, those launchers still do not show up on the radar and cannot be fought until Intelligence ships are destroyed.
• StarCraft II has the Terran sensor tower, which shows enemies beyond visual range as a red exclamation mark symbol. In a twist, it also tells opponents where your tower's detection radius is.
• Total Annihilation has a mini-map that shows enemy buildings and troops once the Fog of War has been lifted. It even makes a distinction between "radar" and "visual range". Radar buildings and units have a large radius and will show incoming enemy units as dots on the minimap, but don't uncover Fog of War.

Simulation Game

• The Ace Combat series has a radar system that varies a little between games. In some games, the color of a target indicates either its point value (Ace Combat 04: Shattered Skies) or whether it's critical to the mission (Ace Combat Zero: The Belkan War), in others it indicates its current health (Ace Combat 5: The Unsung War). Stealth planes generally fade in and out, making it difficult to keep track of them, and aircraft equipped with ECM systems would block portions of the radar or display false targets when close by.
• Escape Velocity has a radar screen. Buying an IFF Decoder will give it colors: non-hostile ships are blue, enemy ships are red, disabled ships are gray, launched fighters and mission escorts are green.
• FTL: Faster Than Light:
  • The Long-Range Sensor augment marks nodes connected to your location with a yellow warning sign if there's a guaranteed spaceship encounter. This isn't exactly useful for evading hostiles as it can throw false positives (some guaranteed ship encounters are completely friendly with no option to turn them hostile) or false negatives (you can end up in what looks like a friendly zone only for all the options showing up forcing you into battle).
  • Both the Slugs and the Lifeform Scanner augment allow seeing the crew on hostile spaceships. They become a tad redundant when you upgrade your ship's sensor, allowing for even more precise imaging of the enemy ships' interiors, but are still useful inside Space Clouds which jam the sensors.
• In the MechWarrior series, radar is a staple of practically every game and is extremely useful in tracking enemies and their damage. 2 and 3 offer the 'satellite uplink' mode, which is more like a bird's eye view of the field. Each game has some kind of mission restriction or equipment to enhance or mess with the radar, including lots of false-positive decoy pods, electronic jammers, and range enhancing probes.
• In Naval Ops series, you have a minimap radar in one corner of the screen and a close-range radar as part of your HUD since trying to spot enemy ships visually is a bit of a pain. Upgrading your ship increases the radar range. Sonar is required to spot submarines. Stealth enemies may not show up on the minimap, but they'll appear on the HUD.
• In Rodina, your HUD displays red rings to pinpoint enemies that are too far to see with a naked eye.
• The X-Universe series has a Gravidar device fitted onto every ship and spacesuit, which can detect anything (bar Space Mines) within its detection radius, which can be expanded with the Duplex or Triplex scanner. Gravidar is shared between ships and satellites, allowing a satellite to be used as a Target Spotter for a missile frigate.
  • The Gravidar returns in X: Rebirth's 2.0 update with some nifty new features; capital ships and stations are now rendered as 3d objects on the gravidar display, and the highway system is likewise shown on the gravidar. Entering a highway will switch the gravidar to a sector-wide highway map, or a tunnel map showing nearby ships in the highway.
• X-Wing and its sequels (TIE Fighter, X-Wing vs. TIE Fighter, and X-Wing Alliance) all feature sensor displays showing any ships nearby using color-coded dots: red for Imperial, green for Rebel, and blue for neutral (or unaligned). Later games add additional colors to represent pirates or otherwise distinguish between multiple unaligned factions.

Stealth-Based Game

• In ECHO, the player character En is surrounded by a holographic sphere made of triangles whose colours rougly indidicate the hostile echoes' distance and alertness level; blue means patrolling, yellow means En is in their field of view, orange means they are alerted by her, and red means she should run.
• A staple of Metal Gear games;
  • In Metal Gear 2: Solid Snake the radar allows the player to see enemies on the surrounding screens. It shows both the guards positions and their vision cones to indicate when you can be seen.
  • Metal Gear Solid and Metal Gear Solid 2: Sons of Liberty both use Soliton radar, which were invented by Mei Ling. Apparently "It employs the KdV equation to detect the electromagnetic waves resulting from biological reactions." It can detect when people yawn, when they close their eyes, which way they are looking, and how far they can see. Triggering an alarm will result in the radar being jammed, as will using chaff grenades, and the radar won't work in enclosed spaces.
  • As a prequel, Metal Gear Solid 3: Snake Eater doesn't feature the radar, as the game is set in a period before it was invented. There's a number of more primitive alternatives that can be found through the game, all of which need battery power. The Motion Sensor will only show moving guards and animals, so a stationary guard won't be shown. The Sonar will indicate everything, but has to be manually triggered and the 'ping' can alert guards. The AP sensor will vibrate when guards are near.
  • Metal Gear Solid: Portable Ops has a Surround Indicator that can mark the direction and proximity of guards according to how much noise they make, as well as how noisy the player is.
  • Metal Gear Solid: Peace Walker does not feature one traditionally, being set just 10 years after Snake Eater. However, you can acquire specs to build your own battery-powered Soliton Radar, continuity be damned, which functions identically to its appearance in previous games. Unfortunately, the battery consumption means that it's all but Awesome, but Impractical until the very last upgrade, whereupon it stops consuming battery.
  • Metal Gear Solid 4: Guns of the Patriots uses a similar Threat Ring, this time surrounding the player in 3D when they crouch rather than in a radar screen. The Solid Eye also gives a radar when worn that works similarly, which shows the position of the player and nearby characters, as well as a second circle around the player that expands or shrinks to indicate how large of a presence they're making themselves through sound and the like; running full-tilt will nearly fill the radar screen, while laying down and blending in with OctoCamo will make the circle only just barely larger than the one indicating their position. The camo index (indicating how effective your camouflage is against your current background) is also worked into the Solid Eye's radar, and will turn blue or red if you're currently harder or easier to notice amidst things like gunfire and mortar shells exploding nearby.

Survival Horror

• The Alien: Isolation radar can detect any moving thing in front of you, be it human, droid, or alien. It also has lights to tell you if something is to your side or behind you, but not how far away it is. However, it cannot tell you if it's on the same level as you, and the beeping might alert other things to your presence.
• Several equippable perks in Dead by Daylight are devoted to showing the "auras" of the characters, which is extremely valuable intel in a game focused on an invulnerable Killer hunting down four Survivors. There's also a few items with relevant add-ons that can achieve the same effect, with the obvious limitation that they can be used up, not to mention lost entirely if the survivor holding them is executed.
• In Enemy Zero, you're on a spaceship out in the middle of nowhere where a bunch of nasty aliens have come aboard and murdered everyone save you and a few others. Problem is, the aliens are completely invisible, and you get to roam the corridors of the ship, completely unable to see them. Your only way of knowing they're around is a sonar-ish device that starts pulsing louder and faster depending on how close the aliens are.
• Fatal Frame has the Camera Obscura's filament and the main character's heartbeat. The filament glows when a ghost is nearby, and glows brighter if you're facing the ghost and/or getting closer to it. The character's heartbeat also speeds up the closer a ghost is. This is quite handy, because it is a common situation that ghost can be near you and you can't see it, either because it's in a wall or it's invisible at the time.
• Freddy Fazbear's Pizzeria Simulator, unlike the other games in the franchise, only has motion sensors instead of cameras to monitor the killer animatronics, presumably because you're just starting out with your pizzeria and can't afford the cameras. Really, though, it's to hide that the 'pizzeria' is a Closed Circle trap for said killer animatronics so they can be destroyed once and for all in the Twist Ending.
• The NES game Jaws includes a radar (unlockable with some seashells) to detect the proximity of the shark.

• The radio in Silent Hill emits ominous-sounding static whenever a monster is lurking nearby, but all it ends up doing is provide Paranoia Fuel since it doesn't tell you how far away said monster is or how many there are. The Variable Mix ambient music/noise also behaves similarly, which may be why they got rid of the radio altogether in the fourth game (except for the one in your room so you can check if it's haunted.

Third-Person Shooter

• Armored Core has this in almost every game, often color coded, but in a bit of a different way; The colors of enemies on radar change depending on their vertical alignment with you (blue for higher, yellow for lower). Starting with Armored Core 4, this system is abolished in favor of a 3D radar, but target enemies show up in red while everything else is white.
  • Noteworthy in that the radar actually has a scan interval between updates. Equipping a rapid-scan radar makes it a lot easier to perform a High-Speed Missile Dodge, since you can trace the missile trajectories even when they circle behind you, but very often there's a tradeoff between fast scan times and longer radar ranges.
• The 3D Grand Theft Auto games have a minimap (sometimes called a radar) in-game. At times, it will show a mission objective or a moving enemy.
• The map of the area you get in every mission in the Hitman games is insanely accurate, even displaying which way doors open, where the fusebox is, and tracking the movement of every person on the premises, Agent 47 included.
  • On the higher difficulty levels, details are removed. On the hardest level, only 47 himself is shown on the map, making the "look through keyhole" action quite handy.
• Mafia despite being set in the 1930s before World War II and the invention of Radar, has one for detecting vehicles in the top left of the screen that shows civilian cars as white, Police as blue and enemies as red blips.
• The video game adaptation of Rogue Trooper shows enemies on a radar at the bottom-left, available as long he is wearing Helm. It doesn't stop enemies from ambushing Rogue when he fires upon the hologram of the traitor general.

• Warframe:
  • Your minimap shows positions and facing of nearby enemies as red arrows that get filled up the more alert the enemy is. Ivara's passive grants her increased detection range by default, and there are mods —both for your warframe and companion— that increase it further.
  • In Exterminate missions, you have a red waypoint which appears when there are no enemies on your radar, showing the way to the nearest one. If there are no hostiles currently detected, it will instead show the way to the extraction zone, which won't be available but moving towards it will guarantee that new enemies will appear.
  • The HUD for archwings and Railjacks marks enemies with squares (or four-armed stars for crewships) that double as their hit point meters. When the enemy is off your field of view, their mark will still appear on the edge of your screen.

Turn-Based Strategy

• XCOM
  • The classic MicroProse series uses two types:
    • On the geoscape, bases need radar arrays (or sonar in the case of Terror From the Deep) to locate UFOs. These come in three sizes with increasing range, and the most advanced type will give detailed information on alien craft and their missions.
    • On the battlescape, troopers can carry a Motion Scanner (Particle Disturbance Sensor in Terror From the Deep) that will detect units that have moved since the player's last turn, even through walls. However, it doesn't tell friend and foe apart, has a very basic display (for instance, a large contact can be either a large unit or a small unit moving quickly), and is rather short range.
  • The Firaxis Games reboot has three:
    • The stand-ins for the old base radar arrays are satellites that can be deployed over the Council countries. They detect UFOs flying over the covered countries, guarantee funding from said countries and are critical to controlling nation-wide panic in three ways: 1) launching a satellite immediately reduces the panic level by two points out of five, 2) at the end of each month they have a chance to reduce panic by one point, and the chance increases the higher the panic level is, and 3) they preclude the Sadistic Choice that is the "Alien Abductions" mission, where you can only help one country out of three. The flipside to these advantages are that satellites take 20 full days to build until very late in the game^note after you research Advanced Construction in the Foundry, you can spend double the money to halve the time to 10 days, require Satellite Uplink or Nexus installations to manage the feeds, and if you ignore a UFO for whatever reason, they can be shot down by a following contact (and instantly raise the country's panic to the breaking point).
    • The Battle Scanner is a round camera-like device that can be thrown like a grenade, and reveals a section of the Fog of War without alarming the enemies it sees; it also blows the cover on invisible⁺ Seekers in XCOM: Enemy Unknown's Enemy Within Expansion Pack, disguised⁺ Faceless in XCOM 2 or concealed⁺ Spectres and the Chosen Assassin in XCOM 2's War of the Chosen Expansion Pack enemies within its area of effect but does not affect the invisibility or concealment of the soldier that deploys it. In XCOM: Enemy Unknown it's normally a Sniper-exclusive Lieutenant skill^note any soldier can get it at any rank with the ability-shuffling "Training Roulette" Second Wave option introduced in Enemy Within and has two "charges" per mission, while in XCOM 2 it's a regular item with only one "charge" developed after performing an autopsy on an ADVENT Trooper.
    • In XCOM 2, Specialists at Sergeant rank or above have access to Scanning Protocol, a skill where they use their GREMLIN to increase their sight radius and reveal disguised or concealed enemy units. It only lasts one turn, though.
  • In both continuities, the Hyperwave Relay is a base structure that complements the radar surveillance with info on the UFO's mission and the species on board.

Western RPG

• Dragon Age: Origins has a Survival skill, and as you gain levels in it, more detail about enemies and higher level enemies will show up. The sequel had all enemies visible on the minimap, but only after you encounter them.
• The Elder Scrolls:
  • Morrowind and Oblivion feature spells like "Detect Humanoid", "Detect Creature", and "Detect Undead". Using them (or applying them as an enchantment effect to an item) will cause the applicable enemy type to show up on the mini-map. Also available are "Detect Magic/Enchantment" and "Detect Key" (presumably the result of a mage losing their tower key once too often).
  • Skyrim has two spells, Detect Living and Detect Dead, which do what they sound like, letting you determine where people are located. The latter is a must-have for draugr ruins to spot where those sneaky undead might be hiding. There's also a Dragon Shout called Aura Whisper that detects everything that can move, living or undead, and has a very wide range and fast cooldown. Once you've got Aura Whisper, you should never fall into an ambush again.
• Fallout:
  • The PIPBoy has a motion tracker option in Fallout and Fallout 2, which will display all living entities on the minimap scanner when it's switched on.
  • In Fallout 3, enemies are shown on your compass as red ticks, with the range governed by your Perception stat.
  • Fallout: New Vegas DLC Lonesome Road has areas where the high radiation levels interfere with your motion tracker.
• The Mass Effect games feature both a radar on your HUD showing hostiles as red triangles, and enemies that can jam it, specifically geth. But the geth radar-jamming is more of a nuisance than anything else: its range is short enough that they only jam you when they're about to attack (meaning they can't really ambush an attentive player), and their flashlight heads are kind of a giveaway as to their location, even in thick fog.
• Might and Magic 6 introduces the "new and improved" automap, which, when combined with the first Air magic spell "Wizard Eye", functions as an Life Detecting Radar - Green is Neutral, Red is Hostile, Blue is Loose Item, and Yellow is Lootable Body.
  • Strictly speaking Blue is 'Point of Interest'. Most of the time that either means a chest or a loose item. Sometimes it is a map-object you can interact with (a fountain that regenerates health, a floor that moves, etc).
• Neverwinter Nights 2 has the Track ability, which pinpoints enemies on the minimap at a distance dependent on your Survival skill. You can toggle it on at the cost of movement speed, or you can take the Improved Tracking feat (free to rangers), which changes it to always-on and allows you to move at full speed.

Wide Open Sandbox

• In No Man's Sky, your enemies are marked on your HUD with red dots, and if they are outside your field of view, their dots will still appear on your screen's edge.
• Your minimap in The Saboteur shows Nazis as red moving dots and their vehicles as approximate shapes. It also shows yellow translucent circles indicating suspicion zones where idling is a bad, bad idea. When you're Dressing as the Enemy, it additionally shows a dashed circle around you indicating a zone where Nazis won't be that fooled by your disguise; it shrinks and grows depending on how fast you move.
• Subnautica: The Cyclops submarine is equipped with one. It will display the location of large creatures relative to the vehicle, and hostile creatures are shown in red.
• In TerraTech, radar blocks can be fitted onto the player's tech, allowing enemies to show up on the minimap as red targeting reticules.

Non Video Game Examples:

Films — Live-Action

• In Aliens, the Colonial Marines use the motion tracker both to look for survivors of Hadley's Hope and hunt for the eponymous Xenomorphs. However, it doesn't discriminate between friend and foe, as shown when the very first thing detected was some hamsters in their habitat; Newt is nearly shot when her appearance on the tracker prompts the Marines to prep their weapons.
• Code Red: the Rubicon Conspiracy has a tracking device which initially is being used to track the remaining survivor, but then inexplicably also tracks both types of aliens.
• In Jurassic World, the park's command center can monitor most dinosaur movements through a combination of infrared and motion sensors, satellite imagery and implanted tracking beacons, the latter of which play an important dramatic role when the Indominus starts raising hell. They even manage to keep track of it after it rips out its implant, probably by following the trail of dino corpses and general devastation it leaves in its wake. It still manages to ambush the heroes on a regular basis despite being a 16-meters murder machine, but then again it's also a genetically engineered Living Weapon with a range of abilities nobody expected it to have.
• In Star Wars: A New Hope, the Millenium Falcon's quad guns are shown to have a sensor suite that shows hostiles as a white chevron shape on a red-and-white double-grid background, which swivels around a circle to show where they are in relation to the ship itself.

Literature

• Harry Potter and the Prisoner of Azkaban has both the Marauder's Map —a real-time map of people and where they are on school grounds— and the Sneakoscope. Though the Sneakoscope only indicates if someone nearby is untrustworthy, whether it's due to a little prank they're playing or something much more serious, with no distinction between the two.
• Krokodil Teares. Smug Californian Op Bronson Manolo's mobile command centre has a readout showing him exactly how many living people there are in the town of Dead Rat with enemies in red and friendlies in blue.
• In the Star Wolf series by David Gerrold, due to the distances involved in a space battle no-one ever sees their opponent. In fact the first novel originally ends with the main character discovering that the enemy spacecraft they've been chasing the entire novel is just a sensor glitch (Gerrold later expanded the novel and had this just be an enemy ploy).

Pinball

• "Locate the Joker" in Stern Pinball's Batman shows Batman using a hand-held sensor to track the Joker as he runs around.

Tabletop Games

• In most if not all Dungeons & Dragons game mechanics (and probably a lot of Tabletop RPGs in general) there are spells to detect the presence, location, and relative strength of a variety of creatures, usually in the form of Detect [Alignment], for creatures matching a particular type of alignment and Detect Undead, for undead creatures. There's also Detect Magic, which doesn't detect creatures, but magical items and spell effects.
• Warhammer 40,000 has the auspex, a handheld or helmet-mounted scanner that can usually detect enemies. Unfortunately (in addition to all the problems with Imperial tech, against the tyranids it sometimes fails due to being calibrated for one species or the other and not hybrids, and sometimes because the 'nids know to stay just out of auspex range when building up their forces for a Zerg Rush.

Webcomics

• In the El Goonish Shive NP open world RPG parody storyline "Fantasy Wasteland", Grace thinks her compass is speciesist for marking the orcs as enemies before she's even tried to talk to them. After making the attempt however, she decides "Okay, fine! My sense of direction can detect hostility, I guess!"

Real Life

• There is a widely-used military system called a Radar Warning Receiver, which (in many, but not all cases) identifies the type of radar emissions (i.e. SPY-1, "High Lark", Agave) and can determine the likely threat of them. A general hint — a repeating tone indicates that an enemy radar emitter has locked on to you and may be getting ready to fire.
  • Want a real life Motion tracker? The closest you'll get in the civilian market is the T-Cube sensor. 500 metre maximum range, with an SOS function, encryption and real time motion detection, the only catch is that you can only see friendlies on your screen. And that it's $500 for two. Take a look.
• Aircraft have something referred to as "IFF", the Identification Friend-or-Foe system. By transmitting certain signals, aircraft can be identified as "friendly", "hostile", "civilian/neutral" or "unknown". This is a way that pilots can quickly identify which aircraft belong to their allies to avoid blowing them out of the sky.

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