Monkey Bomb

The Monkey Bomb, sometimes referred to as the Cymbal Monkey, is the third Wonder Weapon that appeared in Der Riese, and then reappears in Kino der Toten, "Five", Shangri-La and all of the Call of Duty: Black Ops remake versions.

Call of Duty: World at War
The Monkey Bomb first appeared in the map Der Riese, and is only obtainable via Mystery Box. A fairly powerful weapon, it acts as a tactical grenade instead of a gun. It takes a moment to "wind up" the bomb, but when thrown it attracts any nearby zombies and distracts them for seven seconds before detonating.' 

A commonly used tactic is to throw one when a team-mate has been downed, as it will allow the player to pick up the other survivor without much trouble from zombies. While this can be useful, it is still a grenade and may cause zombies to become crawlers upon exploding.

Call of Duty: Black Ops
The Monkey Bomb also appears in the Black Ops version of zombies, it has not changed from the WaW version and it appears in the following maps: Kino der Toten, "Five", Shangri-La (it also appears in all the classic maps) and even Dead Ops Arcade.

Dead Ops Arcade
The Monkey Bomb appears in Dead Ops Arcade but as a power-up and not a weapon and its effect is some what the same as it is on normal maps (when used a big monkey bomb will appear and attract zombies to it). However if a zombie is closer to the player than the monkey it will continue to follow the player, it will only go towards the monkey bomb if the zombies are closer to the monkey bomb than the players.

Call of Duty: ZOMBIES
The Monkey Bomb also appears in the iPhone/iPad/iPod version of the game. It is very similar to its console counterpart, with the addition to affecting hell hounds as well as zombies in this version. In this iteration, the Monkey Bomb is dropped, not thrown.