The N64 version is a non-violent Resident Evil clone (even using the same engine as Resident Evil 2), with the same Tank Controls (though only in the second controller configuration), pre-rendered backgrounds, and fixed camera angles. Unlike the Resident Evil games, the player is able to save wherever and whenever they want, provided they have a Controller Pak.
The player controls Shaggy through four levels, the first three of which are adaptations of episodes from Scooby-Doo, Where Are You!. The basic formula is the same in all four levels: Explore the area for clues and trap pieces and bring them to the rest of the gang, while avoiding the Monster of the Week and other obstacles. Once all of the clues and trap pieces are collected, Shaggy will have to track down the monster and lure them to a specific area to trap and unmask them. All of the monsters are also tied to a mystery involving someone named "R. Necros", which turns out to be the main conflict of the game.
Instead of having a health system, the game makes use of a "Courage" system. When Shaggy comes into contact with something scary, he loses some courage. If he loses all of his courage, he will panic and run away. Courage can be replenished by eating Scooby Snacks scattered throughout the level, or by visiting kitchens (which are only found in the first three levels).
The Game Boy Color version, on the other hand, is a point-and-click adventure game based on a single episode, "Nowhere to Hyde". Playing similarly to Maniac Mansion, you can swap between the members of the gang as they explore Dr. Jekyll's mansion, trying to uncover the truth behind a series of robberies committed by the supposed ghost of Mr. Hyde.
Tropes in the N64 version:
- Adaptation Dye-Job: In the cartoon, Mr. Wickles had black hair and Mr. Greenway had red hair. In this game, both of them have white hair. Similarly, the Black Knight has a blue plume on its helmet, rather than a red one like in the cartoon.
- Adaptation Explanation Extrication: As mentioned below, Professor Hyde-White is omitted from "What a Night for a Knight". As a result, it is never revealed what happened to the driver of the abandoned truck at the beginning of the game.
- During the same level, Shaggy uses a ladder from the top of the Mystery Machine to sneak into the museum through the window. In the cartoon, the Mystery Inc. gang brought the ladder with them when they came back to break into the museum. But since the game only just has them arrive at the museum while following a lead, it makes it seem as though a ladder just happened to be sitting on top of the Mystery Machine when they really needed one.
- In "That's Snow Ghost", a white timber wolf guards the entrance to the cave where Fu Chin Li is hiding. In the cartoon, it was because Fu fed the wolf in exchange for protecting him. But in the game, Fu's connection to the wolf is completely unexplained, making the wolf's presence in the cave seem to be nothing more than a coincidence.
- Adaptation Relationship Overhaul: In the game, Fu Lan Chi (or "Fu Chin Li", as he is called in the game) is the original owner of the Wolf's End Lodge, while Mr. Greenway and Mr. Leech were his employees before Fu was driven into hiding by the Snow Ghost. In the cartoon, Greenway was the owner of the lodge, Leech was another guest at the lodge (though he was actually Greenway's partner in crime), and Fu was a hermit whose tales about encountering a yeti in the Himalayas inspired Greenway to become the Snow Ghost.
- Adapted Out: The game does away with all references to Professor Hyde-White and Lt. Tomoro from "What a Night for a Knight" and "A Tiki Scare is No Fair", respectively.
- Arc Welding: The N64 version adapts "What a Night for a Knight", "That's Snow Ghost", and "A Tiki Scare is No Fair" from the original cartoon into an overarching storyline, where it is revealed that the Black Knight (Mr. Wickles), Snow Ghost (Mr. Greenway), and the Witch Doctor (Mr. John Simms) are all henchmen for a fourth villain known as the Ghoul King (Rex Necros).
- Bat Scare: Bats are a common hazard in the game, even being the first enemies encountered.
- Big Eater: Shaggy and Scooby, of course. Lampshaded by Daphne at the end of the game.Daphne: Don't you guys ever get full?Shaggy: Like only when there's no more food.
- Bigfoot, Sasquatch, and Yeti: The Snow Ghost.
- Black Knight: The villain of the first level, "What a Night for a Knight".
- Blackout Basement: The final part of "A Tiki Scare is No Fair" takes the player through a series of dark underground tunnels. The only light you get are pools of lava inside the tunnels.
- Broken Bridge: The path to the forest in "That's Snow Ghost" is obstructed by a parked snow plow. It won't be until Shaggy and Scooby collect enough clues and trap pieces that Velma will move the plow and you will be allowed to enter the forest to collect even more clues and trap pieces.
- Bystander Syndrome: At the start of "A Tiki Scare is No Fair", Shaggy and Scooby are chased by the Witch Doctor on a beach where several people are present. They don't let this get in the way of their relaxing and sunbathing, though.
- The Cameo: Throughout the game, one can find paintings and other images of Hanna-Barbera characters, such as The Flintstones, Yogi Bear, and Secret Squirrel.
- Canon Foreigner: The security guard in "What a Knight for a Knight", as well as the Ghoul King, were both invented solely for this game.
- Collision Damage: Shaggy only needs to touch one of the many hazards in this game to be scared by them.
- Dagwood Sandwich: Shaggy and Scooby make two of these (one in each of Shaggy's hands) in the kitchens to restore Courage. Shaggy is able to consume both sandwiches in one or two bites each, depending on how many layers the sandwiches have.
- Demoted to Extra: Mano Tiki Tia, the idol the Witch Doctor worships in the episode "A Tiki Scare is No Fair", is reduced to a simple statue that overlooks the secret entrance to the area where Daphne is being held captive.
- Distressed Damsel: Velma in "What A Night for a Knight", Daphne in "A Tiki Scare is No Fair", both (plus Fred) in "The Case of the Classic Creeps".
- Drought Level of Doom: "The Case of the Classic Creeps" is completely devoid of a kitchen, so it's important to conserve the Scooby Snacks scattered throughout the level.
- Every Car Is a Pinto: The crashed truck at the beginning of "What a Night for a Knight" catches fire, so Shaggy has to use a fire extinguisher to put out the flames.
- Everything Trying to Scare You: Not only the Monster of the Week, but also rats, spiders, bats, animatronic dinosaur displays, buzzsaws, zombies, haunted furniture, logs moving along treadmills, even gears and cogs will drain your Courage meter if you come into contact with them.
- Evidence Scavenger Hunt: The game is built on this trope, since part of the main goal of each level is to locate clues (and items that can be used to trap the monster) scattered throughout the level and bring them to the rest of the gang.
- Expressive Health Bar: Shaggy's courage meter has an icon of Shaggy's head which changes depending on how much courage he currently has. He is smiling at full courage, but every time he comes into contact with an obstacle he gets gradually more nervous until at very low courage, he looks completely petrified with hair sticking out on end.
- Great Big Library of Everything: The Wolf's End Lodge in "That's Snow Ghost" has a ridiculously large, maze-like library that could rival most bookstores in terms of how many loaded bookshelves it has.
- Haunted Castle: The fourth and final level, "The Case of the Classic Creeps".
- Lumber Mill Mayhem: Like in the cartoon, "That's Snow Ghost" features a lumber mill.
- Mishmash Museum: The County Museum in "What a Night for a Knight" mostly averts this. It has a Hall of Presidents, a Prehistoric Wing, and an Egyptian Wing in their own separate areas.
- Names to Run Away from Really Fast: Rex Necros, whose name essentially translates to "King Corpse".
- Nobody Here but Us Statues: Happens once in each of the first three levels, provided the player has the required items and is in the right location to use them.
- In "What a Night for a Knight", Shaggy and Scooby can use an Egyptian headdress to hide themselves in the hieroglyphs on one of the walls in a narrow corridor directly in front of the sarcophagus in the Egyptian Wing that the Black Knight comes out of, and can do so the moment he appears. The Black Knight also returns the favor; he will stand on display in the Hall of Presidents exhibit until Shaggy and Scooby come close to him, at which point he will begin chasing them around the room (unless the security guard is already chasing Shaggy and Scooby, then he'll stay put in his original position).
- In "That's Snow Ghost", Shaggy and Scooby can use coal next to a snowman so they can disguise themselves as snowmen to hide themselves from the Snow Ghost.
- In "A Tiki Scare is No Fair", Shaggy and Scooby can use palm fronds to hide themselves in a patch of bushes from the Witch Doctor, which is achieved by standing perfectly still with the palm fronds covering their heads.
- Nobody Poops: Of all the locations in this game, none of them have bathrooms.
- Non-Player Companion: Throughout the game, Shaggy is accompanied by Scooby-Doo (excluding specific areas that Shaggy must enter alone). Downplayed in that Scooby never really contributes anything by being there, ignores and is ignored by enemies and other hazards that would otherwise scare the living daylights out of Shaggy, and the only time he actively participates in something is during the kitchen mini-game, where he throws food out of the refrigerator for Shaggy to catch and make sandwiches with.
- Obstacle Ski Course: There's one in "That's Snow Ghost", that leads back down to the Wolf's End Lodge. Shaggy and Scooby have to lure the Snow Ghost down through it in order to trap and unmask it.
- Palmtree Panic: "A Tiki Scare is No Fair".
- Pirate Parrot: The parrot in "A Tiki Scare is No Fair" will usually utter stock pirate phrases such as "Argh!" and "Shiver me Timbers!" unless you feed him crackers.
- Scooby-Dooby Doors: In "The Case of the Classic Creeps".
- Slippy-Slidey Ice World: "That's Snow Ghost".
- Suspicious Video-Game Generosity: Going into the cafeteria (where there's a kitchen to restore your Courage meter) in "What a Night for a Knight" and coming back out into the hallway will immediately set the security guard on you.
- The Guards Must Be Crazy: If the security guard in "What a Night for a Knight" catches Shaggy and Scooby, he simply escorts them out of the museum without actually arresting them or making sure they don't come back inside.
- Witch Doctor: The villain of the third level, "A Tiki Scare is No Fair".
Tropes in the GBC version:
- Adaptation Expansion: The game takes the plot of the episode it's based on and adds a nephew for Dr. Jekyll, robot guards that look like Shaggy, and Daphne being kidnapped by a oddly familiar Mad Scientist so he can use her as a test subject.
- Cruelty Is the Only Option: In order to progress at one point, Shaggy has to steal Velma's lost glasses and just leave her feeling around trying to find them.
- Eating Solves Everything: When Shaggy and Scooby fall down a trapdoor into the basement, the only way out is to devour an entire wall's worth of cheese, revealing a door behind it.
- LEGO Genetics: One puzzle involves giving the Mad Scientist experimenting on Daphne a relabeled sample of cow DNA to mess up his formula. He tries it and walks away mooing.
- Password Save: The game uses the various symbols seen in-game in various combinations. This is also in-universe as one code that Velma types in at the end of the first stage to get into the lab.
- Secret Room: The lighting and machinery in the lab is powered by an enormous tesla coil in the backyard, but one hidden room is shielded from its effects. This turns out to be a useful way to take down one of the robot guards.
- Scooby-Dooby Doors: Used as a puzzle in Chapter 3, where one of the robot guards chases Shaggy and Scooby through a set of three doors, and the player must choose a fourth one. Whichever door the second one was is the key, hinted by Dr. Jekyll's nephew when he points out a pattern in his game.
- Toilet Teleportation: The mansion's bathroom toilet has a literal teleporter built into it called the "TELEPOT". It sends Daphne to the garage when she flushes it, where Dr. Jekyll promptly kidnaps her for an experiment.
