Gersh Device

The Gersch Device (also referred to as Project Mercury in the Ascension radio messages) is a tactical grenade that appears on the zombie maps Ascension and Moon.

Overview
When thrown, it creates a small singularity that will slowly drag all the zombies that are present on the map towards it, killing them upon impact with the singularity, awarding the player 50 points per zombie (or 130 points if the player holds the Ballistic Knife on Ascension). A player can dive or jump (but not walk or sprint) into the black hole, which will then teleport the player to a random location.

The Gersch Device takes up the player's tactical grenade slot. It is one of two tactical Grenades in Ascension, the other being the Matryoshka Dolls. It is also one of two tactical Grenades in Moon as well, the other being the QED. The player cannot possess both; if the player attempts to take Matryoshka Dolls or the QED, any remaining Gersch Devices will be swapped, and vice versa.

The Gersch Device is an extremely effective weapon to be drawn from the Mystery Box as it can kill a line of Zombies without hassle and gives the players a short break from the zombies. This weapon is also effective if one wants to revive a downed teammate without being attacked (similar to Monkey Bombs). The Gersch Device is a major component of both the Kassimir Mechanism and Richtofen's Grand Scheme Easter Eggs.

Achievement/Trophy

 * They are going THROUGH! - Kill 5 zombies using the Gersh Device - 35G on Xbox/Bronze Trophy on PS3.

Trivia

 * When it is activated, it will start pulling every single zombie on the map, but since it only lasts 10 seconds, it will release them before pulling them in. The closer zombies are to the Gersch Device, the stronger the pull.
 * On Ascension, if the player is holding a Ballistic Knife, the player will receive 130 points for each zombie killed by the Gersch Device, instead of the usual 50 points.
 * The achievement relating to the Gersch device misspells it as the "Gersh" Device.
 * Space Monkeys will run and jump into the black hole willingly. However, this only teleports them and does not kill them.
 * The Gersch Device was the nickname given to "Project Mercury" by the scientist that was working on it at the time.
 * If the player throws a Gersch Device at the ground whilst being in a complex that has multiple levels, the player will usually be teleported one story down, making it an easy way to escape Zombies.
 * According to the radios around the map, the Gersch Device wasn't originally meant to be used as a "black hole bomb", but as a portable teleporter.
 * Sometimes if the player throws a Gersch Device, a zombie will keep acting like it is being sucked into it even if the singularity has closed.
 * Awful Lawton bolts appear to override the Gersch Device. If one shoots a bolt while a Gersch Device is active, zombies will crowd around the bolt instead of being sucked into the device.
 * When a Gersch Device is thrown outside of the playable area (excluding near the generator for the Kassimir Mechanism, or the plates for Richtofen's Grand Scheme) the device will not activate and will not be refunded. While this happens, the player can hear Samantha laughing, just as when the Mystery Box moves.
 * If the player dives to prone using PhD Flopper at the same time someone throws a Gersch Device outside of the map, they will die instantly without being downed.
 * Occasionally, after a Gersch Device is thrown, several zombies will have a delayed reaction. They will not get sucked into the Gersch Device until four to five seconds later.
 * Like the Monkey Bomb before it, Hellhounds are unaffected by this weapon.
 * When in Area 51's cage (activated when a player hacks the Pack-a-Punch) the zombies will be completely unaffected by the Gersch Device, but if the player jumps into it they will still be teleported to a random spot in Area 51.
 * Sometimes in Moon, if a person throws a Gersch Device anywhere an Astronaut Zombie is, the zombie will appear as if it were being sucked in, but it won't die and will do a "Moonwalk" animation with incredible speed.
 * The Gersch Device is used multiple times for the major easter eggs of both Ascension and Moon, the Kassimir Mechanism and Richtofen's Grand Scheme respectively.

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