You play as Dr. Brainula, a man with a brain so big it has helped him to develop a weak form of telepathy. There, he can pick up and punch objects around with his mind (symbolized by your cursor). 

Right click to toggle between cursor mode and fist mode

Toggle: To toggle between modes, right click with the mouse

Cursor mode: Left click with the mouse to pick up Dr. Brainula, and carry him across the level. You can also do this with light objects and enemies also!

Fist mode: Simple swipe with your mouse at an enemy, object, or Dr. Brainula to knock them around the level. Understand that Dr. Brainula cannot be harmed by his own attacks.