As Q*bert, your mission is to claim the pyramids, one block at a time. Starting at the top of each new pyramid, you must hop onto every block, until it is the right color. When all of the blocks of the current pyramid are colored properly, you get a brief moment to celebrate along with some bonus points, before it's off to the next pyramid.
Of course there are a host of enemies determined to stop you, or just to get in your way. Red balls fall randomly down the pyramid, causing major headaches for any Q*bert caught in their path. Purple balls do the same, except when a purple ball reaches the bottom of the pyramid, it stops, and then hatches an evil snake named Coily! Coily can jump up and down the pyramid as he chases after you!
Two other enemies haven't quite grasped the concept of gravity. Ugg and Wrong-Way appear at the bottom-right and bottom-left of the screen, and then hop sideways across the pyramid. Fortunately their movements are random, so you can easily avoid them once you understand how they move.
Slick and Sam are especially annoying, changing the color of any pyramid block they land on. These green pests can be stopped by jumping on top of them, and you even get extra points for doing so. Be careful though, because sometimes it is safer to let them go, rather than risk barrelling through a swarm of red and purple creatures just to save some extra hopping.
Besides two strong legs, you have some tools to help in your quest. Flying disks appear on each side of the pyramid. Jumping off the pyramid is normally suicide, but if you land on a flying disk, you will be whisked back to the top of the pyramid. This is good for evading persistent enemies, but even better, it is an excellent way for disposing of Coily the snake. If he is chasing you closely enough, he will even hop after you off the pyramid, and gravity will take care of the rest. Only a small number of flying disks are offered with each new pyramid, so don't be too careless with them.
Also helpful are green balls that fall occasionally down the pyramid. Unlike red and purple balls, green balls can be safely touched. Even better, grabbing one freezes all on-screen enemies for a few seconds. You can then hop with ease, and even pass through those frozen enemies. Listen closely to the music that plays, for it warns you when the effect is about to wear off.
As you conquer the blocks and reach higher levels of the game, even the pyramids themselves become less and less helpful. Every four pyramids introduce a new level, and a new twist in the challenge to get every block the right color. Level 1 is the easiest and most intuitive, with every block requiring one hop. Level 2 complicates things slightly: the first hop changes a block to an intermediate color, and then the second hop changes it to the destination color. Level 3 ditches the intermediate color, but now if you hop on a block that's already the "final" color, it will change back to the starting color! Level 4 brings back the intermediate colors, so every block again requires two hops, but also, any block with the destination color will go back to the intermediate color if you hop on it again. Finally, level 5 and beyond have the move devious pyramids of all. The first hop turns a block to the intermediate color, and the second hop turns it to the destination color. The next hop turns it back into the starting color, requiring you to hop on it twice yet again! And of course everybody gets faster as the game goes on, making those later challenges even harder!