Throughout the game, you will see little Critters scattered in each level. Suck them up with your Vacuum and collect as many as you can.
There will be checkpoints in certain levels that require a certain number of collected Critters to play a special "mini game". You will need to use your gadgets and intelligence to help a Critter navigate a maze and reach its home at the end of the mini game. Your prize after each mini game win is a piece of the new R.Y.N.O. "weapon".