A Flail of the Unforgiven is an archaic weapon commonly utilised by the leaders of Dark Angels Space Marine Chapter's leaders of the elite cadre known as the Deathwing Knights of the 1st Company, Deathwing. These Knight Masters eschew the usual maces of their fellows in favour of brutal flails. These weapons are carried as a badge of office, and are a reminder to all the Fallen Angels of their ultimate fate at the hands of the Dark Angels.
- Codex: Dark Angels (6th Edition), pp. 45, 62, 81