Hell's Retriever

The Hell's Retriever is a Wonder Weapon and a tactical item introduced in the zombie map, Mob of the Dead for Call of Duty: Black Ops II. The Hell's Retriever can be obtained by feeding multiple zombies to all three Hellhound heads.

The locations of the the three Hellhound heads are as follows:
 * In the 'Broadway' cell block, located near the B23R.
 * In the infirmary adjacent to the Afterlife power box.
 * Near the workbench on the lower level of the docks.

When thrown, it can pierce through multiple zombies at once eventually returning to the player. It can also be charged, which adds more damage and distance. This can be done by holding down the tactical button for a maximum of 2 pulses. If the player throws it towards a Power-Up, it will retrieve the Power-Up and bring it back to the player.

Players will never lose the Hell's Retriever, even if they bleed out. Throwing it does not get rid of it, as it takes a while for it to return to the the player. Additionally, the player has to wait for the 4-second cooldown before it can be thrown again. The Hell's Retriever has the ability to kill zombies instantly (if charged twice) until round 20. It is also very effective when fighting Brutus.

Hell's Redeemer
The Hell's Retriever can be upgraded into the Hell's Redeemer  by completing a series of tasks. As long as it is charged, it is an insta-kill weapon. In addition, it can be charged 3 times as opposed to only twice with the Hell's Retriever.

Steps to obtain the Hell's Redeemer:

 * 1) Fly to the Golden Gate Bridge.
 * 2) Finish one to two rounds on the bridge using only the Hell's Retriever. The player must not kill any zombies with anything other than the Hell's Retriever. Once this step has been successfully completed, the player will hear the noise of entering Afterlife mode at the end of the round. (Note: If the player does kill a zombie something other than the Hell's Retriever, then they must restart with step 1 once they return to Alcatraz.)
 * 3) Return to the prison via an Electric Chair.
 * 4) Throw the Hell's Retriever into the lava pit underneath the Hellhound near the B23R. If done correctly, the Hell's Retriever will not be returned to the player and the Afterlife noise will be heard.
 * 5) Wait for the round to be completed.
 * 6) Enter Afterlife mode and travel to where the Hell's Retriever can be found. The aura of the Hell's Retriever will be now be glowing blue and the player will be able to pick up the Hell's Redeemer.
 * Note: In co-op Zombies mode, every player is able to obtain the Hell's Redeemer. However, they must complete each step individually. Multiple players can attempt each step simultaneously.


 * Note: Regardless if a player is on the bridge trying to complete step 2, the Afterlife noise will still be heard if any other players have successfully completed the step. It could be difficult to tell which players have completed it, so surviving more than one to two rounds on the bridge will ensure that every player has completed it.


 * Note: After you've heard the afterlife sound while you're on the bridge on solo, you are free to use your other weapons.

Trivia

 * The three hellhound heads may be a reference to Cerberus, Hades' triple-headed dog and guardian of the underworld.
 * This is supported by two drawings of three dog heads, one in the cell block and one near the entrance to the Hell's Retriever spawn.
 * The Hell's Retriever can bring dropped power-ups back to the player who threw it.
 * The Hell's Redeemer is the first upgradable tactical item to appear in Zombies.
 * The Hell's Retriever has a fiery appereance whereas the Hell's Redeemer has an ethereal appearence, though it still appears to be composed of molten rock.