Color Keys are objects and low-key puzzles that are used in Shooter and Platformer Games. They were replaced in 3D Mission Game by switches. In the Shooter games, players had to activate the keys (by making contact), and kill a Spider Key foe in order to open access to a door of the same color as the Spider Key. The Key colors in the Shooter games are blue, yellow, and red.
In the Platformer Games, the player has to find the key and make contact (there is no fighting or activating in this process.) with it in order to open access to the door of the same color as the acquired key. Key colors are blue, green, yellow and purple in the Platformer. In 3D Mission Game player has to find and touch a color switch to open same the same Barrier or wall of the same color. In the 3D mission, that are green, orange, and purple. In the shooter, they are red, blue, and yellow. In the Platformer, there is a blue, green, yellow, and purple key. In the PPG, it's a key & door are apart of the Prefabs.
There is a glitch where you get a key & open a door of a different color. All you do is: E.g., if there is a blue door, place a blue key in the game, but place another colored key on top so that the blue key is hidden. When you get the green key, you also get the blue key at the same time, (but at first you don't notice) enabling you to go through the blue door. This glitch works with all colored keys & doors.
Remember: Put the colored key of the door on first, then put a different key on top to hide it.