Successfully complete Story mode to unlock Director's Cut mode.
Successfully complete Director's Cut mode to unlock single player Dual Wield mode in Story and Director's Cut modes. This allows one player to use two Wii-motes with a single health bar. Note: After Dual Wield mode is unlocked, you can use it in any other profile. Simply activate Dual Wield mode in the profile that completed the game, then exit out, and select a profile that has not yet completed the game.
Successfully complete Story mode to unlock extra mutants in Story mode.
Successfully complete Story mode to unlock the Handcannon weapon.
Successfully complete Director's Cut mode to unlock the Minigun weapon.
Purchase and upgrade the Autoshotgun to the maximum level. A single hit on most zombies will kill them.
Successfully complete the indicated task to get the indicated amount of money. Bonuses can only be unlocked once per saved game file. Once collected in Story mode or Director's Cut mode, the same bonus cannot be unlocked in the opposite mode.
At the beginning you will just have a gun. This works better when you have an upgraded automatic shotgun. Shoot the small head as much as possible until you get to the part where the clowns start flipping out. There is a brain in the bottom corner of the box where the first clowns come out to the Boss. Shoot the legs out from the under the clowns while flipping. They will start to crawl. When they are on the ground, attack the Boss.