Chthonian

Chthonian is a monster. It first appeared in the Arkham Horror board game.

Chthonian

Edition(s)	Arkham Horror x2
Movement	Unique
Awareness	+1
Home Dimension	Triangle The City Of The Great Race Unknown Kadath
Rules Text Instead of moving, roll a die. On a 4-6, all investigators in Arkham lose 1 Stamina.
Combat Stats Horror Toughness Combat Rating Damage   Rating Damage -2 2 3 -3 3

Explanation

Chthonians are huge worm like monsters that live under the ground and create violent earthquakes. Instead of moving, this monster is causing an earthquake across Arkham to damage the investigators. As a result, investigators in an Other World are not affected.

Source info

The Chthonians first appeared in Cement Surroundings (1969), written by Brian Lumley.