The first video game from Team Meat (Edmund McMillen and Tommy Refenes) of Super Meat Boy fame, Grey Matter is a 2008 Adobe Flash game billed as an "anti-shooter", due to its inversion of Collision Damage - the enemies do the shooting, and it's your job to ram into them. The theme and general aesthetic of the game is mental illness- you play as a little black dot, representing medicine, and must destroy monsters representing mental illness- but that's really just there to compliment the craziness of the gameplay.
The original can be found here. A slightly updated version was also released as part of McMillen's Basement Collection.
This game provides examples of:
- Big Bad: Mortem Obire, the game's boss, is the last opponent and seems to be the source of the illnesses plaguing the brain.
- Boss Rush: An odd example; Boss Mode only has one boss, Mortem Obire, but the game tracks the time it takes you to beat it, and gives you 100 lives to do so with. Since it makes you do it with minimal upgrades, you'll need a fair number of them.
- Bullet Hell: Not only do the enemies shoot bullets at you, but you actually need to run into them to hurt them, necessitating you getting close to them. Mortem Obire in particular shoots hordes of bullets, especially on Expert mode.
- Collision Damage: Notably inflicted by the player rather than the enemies, and this is your method of attack.
- Energy Weapon: Both the final boss, Mortem Obire, and some late-game enemies use these.
- Evil Is Visceral: The enemies all consist of brains and pieces of bone.
- Flash Step: One type of enemy will avoid you this way. The most reliable way to kill them is to back them into a wall.
- Puzzle Boss: Mortem Obire's body is protected by a
- Rule of Three: Defeating three of the same enemy type in a row will increase your chain multiplier and unleash a trinity attack, which is a triangle with vertices at the three enemies' death positions. Doing this is actually necessary to beat Mortem Obire, who cannot be hurt any other way.