25″w x 31″d x 65″h
QBert, The player controls Q*bert, who starts each game at the top of a pyramid made of 28 cubes, and moves by hopping diagonally from cube to cube. Landing on a cube causes it to change color, and changing every cube to the target color allows the player to progress to the next stage.
At the beginning, jumping on every cube once is enough to advance. In later stages, each cube must be hit twice to reach the target color. Other times, cubes change color every time Q*bert lands on them, instead of remaining on the target color once they reach it. Both elements are then combined in subsequent stages. Jumping off the pyramid results in the character’s death.
The eponymous Q*bert hops diagonally down the pyramid to avoid Coily, who is pursuing him. The game tracks the player’s progress above the pyramid.
The player is impeded by several enemies, introduced gradually to the game:
Coily – Coily first appears as a purple egg that bounces to the bottom of the pyramid and then transforms into a snake that chases after Q*bert
Ugg and Wrongway – Two purple creatures that hop along the sides of the cubes in an Escheresque manner. Starting at either the bottom left or bottom right corner, they keep moving toward the top right or top left side of the pyramid respectively, and fall off the pyramid when they reach the end.
Slick and Sam – Two green creatures that descend down the pyramid and revert cubes whose color has already been changed.
A collision with purple enemies is fatal to the character, whereas the green enemies are removed from the board upon contact. Colored balls occasionally appear at the second row of cubes and bounce downward; contact with a red ball is lethal to Q*bert, while contact with a green one immobilizes the on-screen enemies for a limited time. Multicolored floating discs on either side of the pyramid serve as an escape from danger, particularly Coily. When Q*bert jumps on a disc, it transports him to the top of the pyramid. If Coily is in close pursuit of the character, he will jump after Q*bert and fall to his death, awarding bonus points. This causes all enemies and balls on the screen to disappear, though they start to return after a few seconds.