Infected PlayStation Portable Cheats

$1 Avatar Unlocked

Go to the Customize Officer screen and scroll to the $1 avatar. Hold R and spin him fully around twice, and then stop when he is facing away from you. Then press Triangle, X, Triangle, X, Triangle, Circle. A message will pop up saying "Winner Unlocked!" and kick you back to the main menu. Go back to Customize and buy the avatar.

Unlocking Characters

Unlocking Slipknot and Chimaira:

Unlock Chimaira: Mission 29: Kill one zombie by the chimaira sign.

Unlock Slipknot 0: Mission 5: Kill one zombie by the slipknot sign.

Unlock Slipknot 1: Mission 7: Kill one zombie by the slipknot sign.

Unlock Slipknot 2: Mission 10: Kill one zombie by the slipknot sign.

Unlock Slipknot 3: Mission 13: Kill one zombie by the slipknot sign.

Unlock Slipknot 4: Mission 16: Kill one zombie by the slipknot sign.

Unlock Slipknot 5: Mission 20: Kill one zombie by the slipknot sign.

Unlock Slipknot 6: Mission 23: Kill one zombie by the slipknot sign.

Unlock Slipknot 7: Mission 26: Kill one zombie by the slipknot sign.

Unlock Slipknot 8: Mission 31: Kill one zombie by the slipknot sign.

Unlock Santa Claus or Bloodrayne

The will be unlocked after finish all missions.

Unlock Bloodrayne, Alternate method

Get a gold medal on mission 33.

Easy combos

When you get the chainsaw, combos will become easier. Stand over a Manhole, let the chainsaw rip, and watch your combos go over the top. Ones with lots of enemies around them are recommended, as you can get up to a Ten combo with one slice.