Super Shot: Use an assault rifle with a full reload clip. Hold LT and press Y,Y then hold RT for 10 seconds while still holding the melee trigger. After 10 seconds or more let go of the Melee trigger.
Akimbo Assassin Achievement Made Easy: This achievement requires you to play a whole mission only using pistols. To get this easily start the mission and shoot a few zombies with the pistol only, then choose “Take a break” and let the NPCs finish the level
Unbreakable / Stand Tall Achievements: Do these two achievements on Easy difficulty and get into the habit of running back to let other players (or default AI bots, if on single player) take out the Tanks and enemies. On single-player mode, if a bot accidentally heals you, you can die, restart the map, and not have that count against your achievement. However, this will not work for online play.
Cr0wned Achievement: To kill a witch with a headshot, put the game on Easy difficulty, acquire an auto-shotgun, and look for a witch. As you go after this achievement you should quickly approach the witch with lights off causing her to rise. As the witch is standing unload all 10 shells into her head.
Reload Defense: When reloading any weapon, your survivor can keep attacking with the melee button. This will not interrupt the reload
Fire. Burn this mother down: The infected cannot extinguish fires once they are ignited (all modes even the versus mode). Thus use moltov’s and light gas cans on tough targets such as Tanks and Witches.
Quick Weapon Reload/ Weapon Reset: If you need to 'reset' your primary weapon to its original state, pick up a weapon different from yours, then re-select the weapon you want. This is faster than reloading and can help in close-call rescue finales.
Life is Speed: The Tank can be outrun by any survivor with green health (51% or more), but the Tank can overtake any survivor with 50% of less life, because the more injured a survivor is, the slower s/he moves.
Note: Pain pills will boost the speed of an injured survivor, although the color of the life bar will reflect his/her original health status.
Unbreakable Achievement: The Unbreakable Achievement requires you to not heal yourself or be healed throughout an entire mission. If the computer begins to heal you, whip out your own health pack (DON’T HEAL YOURSELF WITH IT!) and it will stop the computer in its tracks. You can also use Pain Pills for a boost. Finally, if you choose "Take a Break" and let the computer heal you, it won't count against you when you start playing again.
Respawn for Max Health in Versus: If you'd like to refill your health as a zombie, run away from the survivors until you see a message that you are too far away. Press X, and then you'll be allowed to respawn back in the fray with full health. Be aware you are gambling that they won’t make it to the safe room while you do this.
Punch Faster: Alternate tapping the melee button and the weapon switch button rapidly to double your melee speed.
