The Mad Snatcher is an insectoid parasite that has taken control over the body of a human. Interestingly enough, the latter wears a hockey mask, apron, and wields a chainsaw, although no explanation is given whether he already had these characteristics when parasitized, or if it is the result of the creature's will.
It initially remains stationary on its spawning spot; when approached, it takes a moment to turn on its chainsaw and then rushes toward the player while slashing with it.
This enemy is just a modified sprite of the Mad Butcher; the changes are only aesthetic, however, and feature no significant additions to its behavior other than dealing more damage.
"Parasite that clings to, then continually drains its victims."
Same as with the Mad Butcher, the human controlled by this enemy is most likely based on Leatherface, the main antagonist from the horror film series, The Texas Chainsaw Massacre, whereas the hockey mask seems to be inspired by Jason Voorhees, the main antagonist from Friday the 13th. Furthermore, the chainsaw he wields is a shared trait associated with both characters, although the latter has never been seen using one.