The Invincible Reason was a Battleship of the Dark Angels Legion during the Great Crusade and Horus Heresy. The personal ship of Primarch Lion El'Jonson, the Invincible Reason led the Dark Angels effort in the Thramas Crusade.[1]
Sources
- 1: The Lion (Novella) by Gav Thorpe, - The Primarchs (Anthology), pg. 225