Complete mission 3, where you unlock the Rabbid in the controller. Select "Manage Figurines", then enter one of the following codes to activate the corresponding cheat function.
Assassin Rabbid
Hold C + Z and press 2 two times, 1 two times, A two times, 1 two times.
Best Buy Store Employee Rabbid
Hold C + Z and press B, 1 two times, B, A, 2 two times, A.
Best Buy Geek Squad Rabbid
Hold C + Z and press A two times, 1 four times, 2 two times.
Leonardo Rabbid
Hold C + Z and press 1 two times, 2 two times, A two times, 1 two times.
Prince Rabbid
Hold C + Z and press 1, 2, 1, 2, 1, 2, A two times.
Splinter Cell Rabbid
Hold C + Z and press B four times, A four times.
Kangaroo Rabbid
Hold C + Z and press 1 five times, 2, 1, 2.
Chuck Norris reference
Play the "High Stakes Steak" level. Go down the stairs where the first blow Rabbid is located. Enter the room with a pipe and two orange Verminators guarding it. You can find a picture of Chuck Norris on the right wall.