Ice hound

An ice hound was an extraplanar wolf-like creature.

Description
Ice hounds were said to be "cold hell hounds", and were in fact relatives of them.

Combat
These creatures could not be harmed by any cold-based attacks. They were particularly susceptible to fire damage, and thus were often countered by fireballs.

They attacked by using their icy breath, as well as a deadly bite.

Ecology
When summoned to the Prime Material plane, they were often used to protect areas in freezing cold places. As such, ice hounds were known to lurk in the Frozenfar, in places such as Fireshear, Aurilssbarg, Bjorn's Hold, and Icewolf.