At the title screen, use the Right Analog-stick to look down at your hand when you are locked up. Repeatedly press LB + RB to escape the from chair. Move around the lab and find a computer. Type in the command "DOA" to start a zombie killing mini-game. Use Left Analog-stick to move and Right Analog-stick to shoot. Note: You can also enter the command "HELP" at the computer to get a list of other commands.