Boiler

A Boiler is a new strain of Chimera that first appear in Resistance: Retribution and are first referenced to in an Intel Document in Resistance 2. They are exclusively mutated from Human female subjects. Boilers have a rather Human appearance with the exception of an extremely overgrown head in a way that resembles Daedalus. They also seem to have had their hands and feet mutated to resemble tentacles. Furthermore, Boilers greatly resemble Hags, though with a smaller head and a comparatively less feminine face. The Boiler was created for the purpose of invading the warmer African continent. This strain can tolerate warmer temperatures better than most other Chimeran creatures can. There are two known notable Conversion Centers in Europe that converted these strains: Bonn, Germany and the Chrysalis Lair in Paris, France. Within these Conversion Centers, many comatose women flow through the pipes, and it is stated that the women are injected and gassed, mostly whilst suffocating and submerged in water. Also it appears that the Boilers in these unique Centers replaced the workforce of the Menials.

Tactics
Boilers attack by self-destructing while releasing a powerful kinetic wave from their heads. They have hard, leather-like skin, which is durable in gameplay, and the recommended way to kill them is to shoot them in the head. Luckily, the Boilers' heads appear to be very fragile, and will be destroyed easily. You can try to shoot them in the body, but they can withstand much more damage than other basic Chimera, and will take longer to kill.

Trivia

 * It's name might come from their psychic powers, but as the game hints, may have something to do about an incubation that is quite short and similar to actual boiling.