History Main / InUniverseGameClock

* Delphine Software's ''Cruise For A Corpse'' has an in-game clock that only advances when the plot is advanced. Depending on the time, new people may be available to talk to, closed areas may be open, and so on.

* ''Enduro'', by Activision for the Atari 2600, also had day and night, though Enduro's night was based on how far you were into the course and not on time.

* The game ''Sid Meier's Colonization'' takes place over a period of 300 ''years'', with each year being a turn. One year typically takes only a few minutes. Oddly enough, you, the leader of your homeland and the leaders of the other nations/tribes don't get older or die during this time. Ditto, of course, ''Sid Meier's VideoGame/{{Civilization}}'' (4000 BC to usually 2100 AD with increasingly slower increments) and ''VideoGame/SidMeiersAlphaCentauri'' (400 years = 400 turns). At least the latter has the excuse of the faction leaders dipping into the [[PeopleJars Rejuvenation Tanks]] for a couple months out of every decade.

* In the FreewareGame ''Survivor: The Living Dead'', every single gameplay mode is tied to a clock (except one short area in the story mode), when the timer runs out you get rescued. The final unlockable mode has no rescue, and you must survive until sunrise.

* ''VideoGame/{{Calico}}'' has changing day/night in its world, complete with different day/night songs for each of its six areas. The time of day tends not to affect the behavior of townspeople much.

* Another EasterEgg in ''VideoGame/ShadowOfTheTombRaider'': if your computer clock shows that it is the 14th of February, loading screens in-game might display "happy birthday Lara Croft" instead of the usual tip.

* ''VideoGame/XenobladeChronicles1'' has the usual 24-hour clock with one second being usual one minute, and most named [=NPCs=] are only available at specific hours and some monsters only spawn at specific time of the day. Considering how many [=NPCs=] there are and how many of them have sidequests associated with them, it's a mercy that you can change the ingame time at will. There's also an ingame achievement called "Happy New Year!" for seeing a total of 365 sunrises. ''VideoGame/XenobladeChroniclesX'' has the exact same system.

* {{Creator/Sierra}}'s ''VideoGame/QuestForGlory'' series would close stores, bar the city gates (whether you were inside or out), and put most civilians to bed past certain hours. This was also the only time thief characters could get in their looting. Furthermore, the series also kept track of the number of days elapsed and would advance the plot accordingly; beating the game was usually not possible until key events occurred several days in. An unnoticed time-keeping bug in ''VideoGame/QuestForGloryIII'' unintentionally ''forced'' the player to be in a certain city on a certain day to take part in an important plot point; if the player missed the event, it would not reoccur -- and the game would not be able to proceed.

* Leads to awesome FridgeLogic in ''VideoGame/RollerCoasterTycoon'' when you realize that your park guests have been standing in line for ''months'' without eating, sleeping or going to the bathroom. Also worth noting is the game's calendar, which starts at March and ends at October, as per a theme park year. This only serves to compound the FridgeLogic, as you realize that between October of one year and March the next, literally nothing happens. R&D completely shuts down, Advertising takes a break, and [[ArsonMurderandJaywalking those guests are still standing in line]].

NPCScheduling is a subtrope. VideoGameTime is a common effect of this.

** While some game mechanics in ''VideoGame/PokemonScarletAndViolet'' are tied to real-world/system time such as the daily Tera Raids and Mass Outbreaks, the games use an in-game clock for their day/night cycle like ''VideoGame/PokemonLegendsArceus''. One full cycle lasts 72 minutes: 3 for morning, 33, for day, 3 for evening, and 33 for night. This affects the kinds of spawns you encounter and when you can evolve certain Pokémon. However, unlike in ''PLA'', you can't [[FastForwardMechanic fast-forward time to the next morning, day, or night.]]

* Oddly enough, an [[WhatCouldHaveBeen early version]] of ''VideoGame/SonicTheHedgehog2006'' had a day/night cycle. There was a video or screenshots where this was shown off; as the sun travels through the sky, the real-time shadows under Sonic's feet, and the ones produced by the random crates and the tree, are quite breath-taking.

* Koei strategy game franchises such as ''VideoGame/NobunagasAmbition'', ''VideoGame/RomanceOfTheThreeKingdoms'' and ''VideoGame/GenghisKhan'' often feature in-game clocks where time passes very quickly, often in terms of entire seasons and years rather than just days.

* If you played ''VideoGame/MudAndBlood'' 2 on Halloween,[[https://www.youtube.com/watch?v=90TW-p3rkQk Nazi zombies]] would be added to some of the German waves, and if you played on Christmas, Santa Claus would appear on the battle map ([[DownerEnding and possibly get killed in the crossfire]]).

# In-game time advances with the system clock, or X times faster than the system clock--in the extreme case of some God Games, a game year may take [[YearInsideHourOutside only an hour to play]].

# Changes the types of monsters that appear, or which [=NPCs=] [[NPCScheduling can be encountered]].

* A full day cycle in ''VideoGame/{{Minecraft}}'' lasts 20 minutes (equal to 72:1 time compression). Above-ground, monsters generally only spawn at night, so keeping track of time is important. In single player, you can skip the night by sleeping in a bed, so long as there are no hostile enemies nearby. It works in multiplayer too, but you need everyone on the server to go to bed in order to skip time. The Nether and the End realms doesn't have any form of time at all, so when you attempt to sleep in a bed in those places, [[MadeOfExplodium ''your bed explodes.'']] The cycle continues running in the overworld while you're in one of the underworlds, though you'll have to use an external clock to know whether it's day or night, because the in-game clock item just spins chaotically.

* A full day cycle in ''VideoGame/{{Minecraft}}'' lasts 20 minutes (equal to 72:1 time compression). Above-ground, monsters generally only spawn at night, so keeping track of time is important. In single player, you can skip the night by sleeping in a bed, so long as there are no hostile enemies nearby. It works in multiplayer too, but you need everyone on the server to go to bed in order to skip time. The Nether and the End realms doesn't have any form of time at all, so when you attempt to sleep in a bed in those places, ''your bed explodes.'' The cycle continues running in the overworld while you're in one of the underworlds, though you'll have to use an external clock to know whether it's day or night, because the in-game clock item just spins chaotically.

* ''VideoGame/PokemonGoldAndSilver'' started the series' tradition of built-in clocks that segregate the day into three time periods -- morning, evening, and night -- as well as keeping track of a seven-day week. In order to complete certain events or capture certain Pokémon, you must play the game during those time periods. The in-game time is entered when a new save file is started and kept using a watch battery present inside the game cartridge. For some unexplained reason, the day-night system was removed in ''VideoGame/PokemonRubyAndSapphire'' even though those games also track real time based on the time entered by the player at the start of the game. The only feature affected by the time of day is Eevee, which evolves into either Espeon or Umbreon based on whether it's day or night. ''[=FireRed=]'' and ''[=LeafGreen=]'', being [[VideoGameRemake remakes]] of ''Red'' and ''Blue'', removed the in-game clock entirely, and as a result Eevee can never evolve into Espeon or Umbreon; those Pokémon have to be traded in from ''[[VideoGame/PokemonColosseum Colosseum]], [[VideoGame/PokemonXDGaleOfDarkness XD]], [[VideoGame/PokemonRubyAndSapphire Ruby, Sapphire]]'', or ''[[VideoGame/PokemonRubyAndSapphire Emerald]]''. ''VideoGame/PokemonDiamondAndPearl'' brought it back, but since the UsefulNotes/NintendoDS has an internal clock, they used that instead.

* ''VideoGame/PokemonSunAndMoon'' will always start in the daytime or nighttime, respectively, regardless of the time of your system clock. The next plot event will always take place at sundown. Story-wise, it's not until the third day that the in-game time correlates to that of your system clock. This extends to ''VideoGame/PokemonUltraSunAndUltraMoon'' as well. In addition, in the former games, when you [[spoiler:go to summon the cover legendary]], if it's nighttime in ''Sun'' or daytime in ''Moon'', the game will skip to day or night, respectively, and will return to normal once that plot event is over.
* ''VideoGame/PokemonSwordAndShield'' takes an even weirder strategy than ''Sun and Moon'': the in-game time of day is plot-based ''except'' in the "Wild Area," the vast expanse of Pokémon-hunting grounds, where the time always matches your system clock. So, if you leave the Wild Area to heal at a Pokémon Center and head out again, the apparent time can switch from night to day and back again, or vice versa. After you finish the main storyline, all locations follow system-clock time.

* The ''VideoGame/EtrianOdyssey'' series has a day-night cycle, as well as an in-game calendar (for instance, the guild always starts its adventures on Emperor 1). Time advances as you explore the Labyrinth, and when sleeping at the inn, you can choose to be awakened in the morning or evening. Depending on the time of day, different monsters may appear in the Labyrinth, or [=FOEs=] may behave differently. In some areas, however, this behaves oddly. For instance, in the third game, sailing around quickly eats up hours, and reaching different destinations can easily take a day or two. However, Sea Quests don't take any in-game time at all -- the guild is simply deposited right at their destination for the BossFight, then returns to Armoroad for their rewards without any time elapsing. In fact, the clock even ''reverts'' to whatever time it was when you started the quest even if the battle took a few in-game hours!

* ''VideoGame/{{Fallout|1}}'' ran real-time on area maps, but with time compression while traveling on the overland map. ''VideoGame/Fallout3'' and ''VideoGame/FalloutNewVegas'' used the same time compression scheme as Oblivion, having been built on the same UsefulNotes/GameEngine.

* ''VideoGame/{{Terraria}}'' has an ingame day cycle that lasts 24 minutes every full cycle, there are also moon phases that can affect what items are available from the NPC's, including the blood moon where monsters swarm the player. Some bosses can only be summoned to be fought during the night. Should dawn occur in game, the respective bosses flee/instant kill the player, there is also accessories that tell the time as well as a grandfather clock that does so when right clicked, as well as a magical Sundial which will skip time ahead by 24 hours and can be used once an in-game week.

* ''VideoGame/{{Starbound}}'': Each planet has its own day/night cycle, which can be longer or shorter depending on the planet. Your ship will match that of the planet it's orbiting. It's largely cosmetic, though for obvious reasons it's a bit harder to see where you're going at night; also, birds become hostile at night for no apparent reason. Some mods impart other effects depending on the time, such as desert planets' heat sapping your health during daylight hours.

** The 24-minute day/night cycle gets a [[LampshadeHanging lampshade]] ''[[JakIIRenegade Jak II]]''. After completing a specific Mission, Krew says it's time for his beauty nap, to which Daxter replies that there aren't enough hours in the day.

* ''VideoGame/MarioParty 6'' has a turn-based day-and-night system. Every 3 turns, the time of day changes. Depending on the time of day, certain routes will become available or unavailable, prices at stores change, and some board events will be different. Even some of the minigames will have altered gameplay.
** Likewise, Horror World in ''VideoGame/MarioParty2'' operates on this same mechanic, though unlike the sixth game, it has a strong preference for nighttime, owing to it being the board for Boos. Stepping on a Happening Space also turns day to night, or vice versa.

* ''VideoGame/PokemonSunAndMoon'' will always start in the daytime or nighttime, respectively, regardless of the time of your system clock. The next plot event will always take place at sundown. Story-wise, it's not until the third day that the in-game time correlates to that of your system clock. This extends to ''VideoGame/PokemonUltraSunAndUltraMoon'' as well. In addition, in the former games, when you [[spoiler: go to summon the cover legendary]], if it's nighttime in ''Sun'' or daytime in ''Moon'', the game will skip to day or night, respectively, and will return to normal once that plot event is over.
* ''VideoGame/PokemonSwordAndShield'' takes an even weirder strategy than ''Sun and Moon'': the in-game time of day is plot-based ''except'' in the "Wild Area," the vast expanse of Pokemon-hunting grounds, where the time always matches your system clock. So, if you leave the Wild Area to heal at a Pokecenter and head out again, the apparent time can switch from night to day and back again, or vice versa. After you finish the main storyline, all locations follow system-clock time.
* The Super NES RPG ''VideoGame/RudraNoHihou'' uses this, with a single plot set across 16 days and nights and following three different characters, all coming together at the 14th day for the finale.

** ''VideoGame/PokemonSunAndMoon'' further expanded on this. ''Pokémon Sun'' has the time in-game actually matched to the system clock but in ''Pokémon Moon'' the time is offset by 12 hours from the system clock. Once again the player will encounter different Pokémon depending on whether it is day or night.

* ''VideoGame/Persona3'' and ''VideoGame/Persona4'', mostly due to your protagonist's regular schedule of WakeUpGoToSchoolSaveTheWorld. The game announces when the "clock" progresses to the next time of day (or the next day).