Gideon is a Black Templars Marshal, who lead the Chapter's Mephistari Crusade.[1] Later he took part in the Indomitus Crusade Fleet Secundus' Battle Group Erastus where with Emperor's Champion, Abbess Vahl of the Bloody Rose, and Baron Munstis and his Imperial Knights of House Fidelitor he defeated the Witch-Empress and her daemonic patrons on Vastoros.[2]
Source
- 1: Warhammer 40,000 8th Edition Rulebook, pg. 50 — Dark Imperium
- 2: Codex: Black Templars (9th Edition), pg. 25 - Heimdel Crusade