The player must collect all hearts in order to open a treasure chest and collect the gem inside, which will open the exit to the next level.
The player must navigate the obstacles in each level and avoid or neutralize several different types of enemies, which vary by movement and attack pattern. All enemies disappear once the player picks up the gem.
The player can move, slide certain blocks around the level, and fire a limited number of shots at enemies. When an enemy is shot, it becomes an egg for a short time; this can be pushed to a new location, used as a bridge to cross water, or shot again to make it disappear temporarily. Some enemies are not affected by the player's shots.
The player’s life is lost whenever the player is shot or touched by certain enemies, then the level will be restarted. Some enemies will not kill the player, but can impede his movement by standing still or freezing in place when touched. The player can restart a level at any time, when it’s impossible to complete it.