Defeat Zombogod.
Defeat Zombogod with perfect life.
Have the Rocketeer kill 500 zombies.
Have the Gunner kill 500 zombies.
Kill 1500 zombies in total.
Have the Sniper shoot 750 bullets.
Have the Rocketeer shoot 500 rockets.
Use Bomb of Duty 50 times.
Have the Sniper kill 500 zombies.
Have 500 critical shots in total.
Use Time Machine 35 times.
Have the Gunner stun 200 zombies.
Use Air Strike 20 times.
Kill 100 giant zombies.
Kill 100 flying zombies.
Rescue 15 refugees in total.
Have the Sniper shoot through 100 zombies.
Have the Rocketeer shoot 50 extra rockets.
Have the Gunner shoot 1000 bullets.
Fully upgrade all characters.
Unlock the Rocketeer.
Acquire all gems.
Unlock the Sniper.
Have 10000 gold.
