In one room you need to bounce on three drums to reach a high ledge and the exit. In another, you have to negotiate your way through swinging diamonds. In another, you have to jump across constantly sliding panels and avoid falling to a molten death far below. And so on. Through the vast majority of these rooms, you'll simply move and jump.
Timing is everything.
Occasionally, you'll have to fight an enemy or two. The most popular of your foes is a little masked guy wielding a wicked club. Others include leopard men, tough lava men, and different types of flying menaces. None of these is all that difficult to take out. Damage is earned from both your enemies and from falls.