Kill at least 1.000 zombies with each weapon type.
Stay alive at least 60 minutes.
Kill 500.000 zombies.
Explode atleast 100 cars in one session.
Rack up to 30 level.
Get 10.000.000 experience points in the single session.
Kill first Undead Boss.
Don't shoot for whole six minutes and survive.
Perform a rampage attack.
Use melee attack 100 times in one session.