The Ghost faces have been known to use violence against anyone who is not themselves. Raiding parties of over 100 warriors sometimes travel down the main river in canoes raiding nearby tribes. 12 years before the 6th Brotherband book, a Skandian wolfship, the Wolf Foot, was raiding the West coast of Hibernia. A large storm blew them off course into an unknown land deep in the Endless Ocean. The skirl of the Wolf Foot, Arnulf Sharkfighter, and most of the rest of the crew were killed by the Ghost faces. The only survivor, Ovik Eelcatcher, lived with the passive Mawagansett tribe to the south.
In Brotherband Book 6: The Ghostfaces, the tribe plays a central role, and kills a (as of yet, unidentified) member of Hal Mikkleson's Brotherband