One Inch Punch

The One Inch Punch is a melee upgrade that replaces the player's standard knife in the Zombies map Origins. It allows the player to punch zombies with a powerful force, causing zombies to fly away, similarly to the Thundergun from Call of Duty: Black Ops. It can kill a zombie with a single melee attack until round 19.

In order to obtain it, the player must charge up four chests that are located throughout the map, by killing 30 zombies near them. If a Giant Robot steps on a chest while it's not yet full, it will be reset, and the players will have to kill more zombies. Once completed, players can go to a Rituals of the Ancients station and they will be rewarded with the One Inch Punch, in the form of a glowing energy ball.

The four chests are located as follows: one is in the Robot footprint next to Generator 5/Stamin-up, another is in the Robot footprint to the left of the first entrance to the excavation site, another is in the Robot footprint to the right of Generator 4/Juggernog (not the footprint containing the wind portal), and finally one in the Robot footprint outside the Church, on the side closest to the excavation site. Each chest must be filled with 30 zombie souls. Odin (the Giant Robot who patrols the center of the map), is a major hindrance, as he has the potential to close three of the chests in one go.

Should a player bleed out and lose their One Inch Punch, or otherwise not be present in game when the chests are completed and the Punch is unlocked, the player in question must simply go to a Ritual of the Ancients station, highlight their crosshair over the bottom-most medal, and press the action button. The Punch will then be re-obtainable for the player.

Iron Fists
The One Inch Punch can be upgraded during the Little Lost Girl easter egg, after hitting roughly 20 Templar zombies with glowing arms in the staff room with the One Inch Punch. After reaching the amount, a power-up resembling a stone for the G-Strike will be dropped. It gains a one hit kill attack until round 36 and has an extra elemental attack depending on which staff the player was holding at the time of the pickup; for example, players with the Fire Staff will set zombies on fire with their punches. The steps to done to unlock Iron Fists are a referance to the mission in COD: Black Ops in which Mason and Reznov make the attempt to escape Vorkuta.

Elemental Knife
This a glitch that can only be done in multiplayer, and will give the player the same properties of the Iron Fists, but instead of the punching animation, the player uses the regular knife to attack. The elemental bonus from the Iron Fists remains. It is much more powerful than the Iron Fists allowing a 1 hit kill up until round 68.

Trivia

 * The One Inch Punch is a reference to a martial exercise move of the same name in which a person is knocked back several feet from a punch only one inch away popularized by actor and martial artist Bruce Lee.
 * When upgraded, if the player punches a glowing Templar Zombie with it, they will stop glowing.
 * To gain kills toward the Iron Fists, the actual kill does not have to be from the One Inch Punch. The initial hit will cause the Templar Zombies to lose the glow on their arms, and this counts toward the reward.