It is an enemy that will appear every few minutes in Suicide Mode and is one of the most dangerous non-boss enemies in the game, constantly swinging both its chainsaws around regardless of what is nearby, killing Players and enemies alike.
The creature is extremely fast and very durable, with an above average amount of health. If it manages to catch the player, it can kill them in one hit. Bear in mind that while this makes it a priority to avoid, it can be utilized to kill other monsters in Suicide Mode due to its keen lack of discretion towards what it kills with its chainsaws.
The monster previously made a single appearance in the official single player campaign following the 1.3 patch, appearing on the narrow pathway between the TL Trading building and the door towards the apartments where Sophie is encountered. However, it was removed following the 1.35 patch and taken out of the single player campaign entirely.
It also makes five appearances in the official co-op campaign. Its first appearance is in Kirkville at the beginning of the game, appearing on the second portion of the map upon exiting the parking garage. The second encounter is at the beginning of the forest segment in an abandoned shack, inside a room stocked with weapons. The third location is in the asylum on the second floor, close to the doorway the players must go through to progress out a nearby window. The fourth encounter is in the lower levels of the subway upon reaching the city where it is fought alongside several suiciders. The fifth and final fight is in the cramped hallways of the TL Trading lower floor. One can also meet this monster in the Manhunt campaign.
The monster's lack of discrimination is not related to Simon in any way.