Breacher Siege Space Marine
These troops were specially trained and equipped for hazardous assault operations such as boarding enemy vessels or launching the first wave of attack on fortifications. They were commonly equipped with heavy Boarding Shields and specialized assault weapons such as Graviton Guns, Lascutters, Volkite Chargers, Flamers, and Melta guns.
- Phalanx Warder - Imperial Fists
- Medusan Immortals - Iron Hands
- Praetorian Breacher Squad - Ultramarines
- 1: The Horus Heresy Book One - Betrayal pg.204
- 2: Forge World (saved archive page, dated April 2015, last accessed 20 February 2020)
- 3: The Horus Heresy Book Five - Tempest, pg. 89