General Mantis

General Mantis is a Crenga - a genderless species - and a "villain" in the Skulduggery Pleasant series. Mantis is tall, pale, with long arms and legs, and wears a gas mask. Mantis is the primary antagonist for the first part of Last Stand of Dead Men.

Mantis is not technically a villain, as he does not commit "evil" actions from his, or his peoples point of view, and is merely on the opposing side of the main characters.

The War with Mevolent
During the war with Mevolent, General Mantis was one of the top tacticians for the allies. Due to it's incredible tactical genius, the allies never lost a battle while Mantis was in command.