The 25th Founding of Space Marine Chapters occurred during the latter half of the 40th Millennium. There are only two known Chapters that were Founded at this time -- the Fire Angels and the ill-fated Star Scorpions. The Fire Angels were created during this period, Founded as a Chapter without a specific named predecessor Chapter. Instead they were created from a gene-stock issue, their initial command and training structure composed of honoured Veterans drawn from several Ultramarines Successor Chapters. Their gene-seed is also on record as being sourced from the highly stable Ultramarines stock.
The Star Scorpions were also created during this Founding but had the dual misfortune of producing highly mutated gene-seed and being utterly devastated by daemonic entities when the Chapter's fleet became trapped in the Warp. The exact fate of the Star Scorpions is unknown. However, the High Lords of Terra decreed on the Emperor of Mankind's behalf that the Chapter should be considered irrevocably lost when the Adeptus Mechanicus proved incapable of using their corrupted gene-seed to reconstitute the Chapter.
Select 25th Founding Chapters
- Imperial Armour Volume Nine - The Badab War - Part One, pp. 47, 50, 90-97, 168
- Imperial Armour Volulme Ten - The Badab War - Part Two, pp. 13, 19
- Warhammer 40,000: Compendium (1st Edition), "The Badab War" by Rick Priestley, pp. 33-35
- White Dwarf 103 (UK), "Rampaging Rhinos" by Rick Priestley
- White Dwarf 101 (UK) "Index Astartes: The Badab Uprising" by Rick Priestley
- White Dwarf 98 (UK), "Index Astartes - The Mentor Legion"