Control the virus's movement with your mouse, run over the smaller viruses and consume them. Learn to split your virus by pressing Space (once you've accumulated enough mass).
Tired of being good and petting kitties? You've got a chance to become the biggest, mightiest and most vicious virus on the server. All you need to do is eat humans and the weaker viruses. Avoid sanitizers, they will tear your virus apart! Will you be able to stay alive for at least five minutes in this strange world or will other viruses eat you? Play and find out!