Steg the slug has to feed his family of “T’yungunz”. To do this he must blow
bubbles to catch the grubs that they feed on and guide them through the level
by blowing on them or nudging them past any obstacles in the way to the nest
where T’yungunz live. To complete a level, you must make sure that a certain
number of T’yungunz are fully fed so they go to sleep. If they don’t get
enough food then eventually they die.

The levels are full of contraptions such as bellows, and obstacles such as
spikes and fire that will burst the bubbles. Some of these can be activated or
deactivated using various switches.

Usually Steg navigates each level by walking on the floor, and also he can
climb up the walls and even walk on the ceiling. There are also devices he can
contruct out of the parts from the Acme Bionic Bitz Catalogue, such as the
Rocket Pack, and Bionic Legs, which allow different ways of getting around
each level.