Green tiles make a sound. They supposedly force the protagonist to fight a monster, but in the puzzle's first appearance, they don't appear at all, and in the second, it is only used as an excuse for Mettaton to fight after the puzzle is completed or ended.
Red tiles act as solid walls.
Yellow tiles force the player back to the last tile they stepped on (the player's controls are locked in the meantime).
Orange tiles change the player's flavor to "Orange".
Purple tiles act similarly to the ice tiles in Snowdin; they force the player to the next tile in the direction they are facing (the player's controls are locked in the meantime). Additionally, purple tiles change the player's flavor to "Lemon".
Blue tiles vary in function depending on the following factors:
If the blue tile is adjacent to a yellow tile, the blue tile acts identically to a yellow tile, simulating electrified water.
If the player's flavor is "Orange", the blue tile also acts identically to a yellow tile, luring the piranhas out and forcing the player back to the previous tile.
If neither of the above conditions are met, the blue tile acts identically to a pink tile.
Main story
Multicolor Tile Puzzle screenshot.png
Papyrus's Multicolor Tile Puzzle during generation
In the first encounter, Papyrus presents the puzzle to the protagonist and explains the rules. However, the "randomly generated" outcome the machine creates is simply a line of pink tiles bordered by red tiles, which the protagonist can walk right across without trouble. Later, investigating Alphys's computer in her Lab reveals that it is "accessing some kind of puzzle in Snowdin", implying that she rigged the puzzle for the protagonist.
If the protagonist says they do not understand Papyrus's explanation of the puzzle's rules, he gets confused and mixes up the rules. If the protagonist again says the explanation makes less sense, Papyrus grows irritated and leaves a note explaining the rules, so to let the protagonist activate the machine themselves. The note contains illegible chicken scratch,[2] and the machine cannot be operated.[3]
On the Genocide Route, Papyrus becomes annoyed at the protagonist for walking through the puzzle and eventually gives up trying to explain it. He leaves a note with chicken scratch similar to the note when the protagonist says they do not understand the rules twice.
Multicolor Tile Puzzle solution.png
Solution to Mettaton's tile puzzle
In the second encounter, Mettaton makes the protagonist fall through a trap door containing the puzzle. He then starts to explain the rules, but instead says, "DIDN'T WE SEE THIS PUZZLE ABOUT A HUNDRED ROOMS AGO? THAT'S RIGHT. YOU REMEMBER ALL THE RULES, DON'T YOU?" and starts the puzzle, giving them 30 seconds to complete it or else they will be burned by a pair of walls of fire.
If the protagonist does manage to solve the puzzle, Mettaton deactivates the flames before deciding to fight the protagonist. If they do not solve the puzzle, the walls of fire draw near before Alphys disables them; Mettaton then fights the protagonist, as he is the monster summoned by the green tile. If the protagonist does not step on a green tile, Mettaton fights them anyway.
* Honestly I'd love to see the multi-color tile puzzle expanded on in literally any way (except for with a timer I need time to think about things like that so the Mettaton one doesn't count)