Asterion Moloc
Asterion Moloc is the Chapter Master of the Minotaurs, and one hardass motherfucker.
Lord Asterion Moloc (how he wishes to be called) takes an almost perverse glee in stabbing dudes in the face with the Black Spear, a weapon that may or may not be based on a Adeptus Custodes halberd. And instead of having a bolter strapped to the underside it has an in-build laser to vaporize dudes. Lord Moloc himself is a huge dude riddled with cybernetic augmentation that allows him to ignore even more wounds than he already could with his simmering rage. Despite him often being on the battlefield alongside his Terminators stabbing dudes in the face, he has a ruthless mind for warfare, siegecraft, logistics and strategy.
Lord Moloc's favorite enemy is fellow Space Marines, and he has become frightingly efficient at it. The large amount of high-end equipment used by the Minotaurs combined with them almost always deploying at full Chapter strength means that the Minotaurs have a good shot at kicking heretic ass, as the Lamenters and Inceptors can attest. Because of the full deployment Lord Moloc is always in charge of the Chapter in entirity, meaning that in battle his captains are little more than his seconds.
There seems to be something strange going on with Lord Moloc. During the Orphean War he fought against a Necron Lord in a Necron vessel. Moloc got his ass kicked and was spaced. While normal Marines would be noted as KIA and a new Chapter Master would be chosen. Instead his body was recovered and he was nursed back to health. This is at least the seventh time that Lord Moloc was critically injured in battle yet he lived to fight another day in five centuries, suggesting that his name and equipment are inherited by the next Chapter Master, alongside his personality through way of engrammatically-enforced memories and personality.
On the battlefield he is incredibly expensive to field (just as much as Lugft Huron and just under The M.A.C. Daddy's point cost. In return you get a beast in Terminator armor with 4 wounds, a Storm Shield, a S6 AP2 weapon that strikes in Initiative order, Frag Grenades and all the goodies you expect from a Chapter Master. He also gives his squad Fearless and Frag Grenades through his special rule, meaning that somehow he wills fragmentation grenades into being through nothing but his sheer RAGE, which is something that even the Angry Marines have to respect.