Gersh Device

The Gersch Device (also referred to as Project Mercury by Dr. Gersch) 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! (35 / Bronze Trophy ) - Kill 5 zombies using the Gersh Device on Ascention.

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. Zombies closer to the device will be pulled more strongly
 * 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 Gersh.
 * 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.
 * 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.
 * Awful Lawton bolts appear to override the Gersch 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.
 * Like the Monkey Bomb before it, Hellhounds are unaffected by this weapon.
 * If all players are inside 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. however if at least one player is outside of the cage, gersch devices will still work normally but they must be thrown above the cage
 * 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.
 * Nikolai refers to the Gersch Device as a "big let down device" on Moon.
 * The round that the device throws is similar to the pipe bomb in Left 4 Dead.

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