There is a hive mind structure to Grimm activities and behavior; some claim that it is actually a human that pulls the strings.
Sculpted by Christian Danckworth, this is another of the first set of Grimm. These characterful little under-dwellers make frequent forays to the surface world under the bidding of their master.
The (currently available) Grimm can be fielded in a couple of ways: they can be used as Minions to be taken by any Faction; or they can be used as a Resource that provides some kind of boost, however this requires the presence of a Grimm Master or Superior Grimm Master in the same Team (Guide; Errata p. 137).
The Grimm Digger adds Immunity to Difficult Terrain and Ram to the abilities of a card of Grimm Minions.