Eshmunazar, one of the non combat Astartes. Astartes veteran of the long war (10th Host all the way). Commander of the Verbum.

More machine than man now, spent time in stasis after sustaining injures during the 11th black crusade. Had the host had Dreadnought hulks available he would have been a candidate. Doctore fixed him up as good as can be and the rest was done as part of the hosts old pacts with Mechanicus in the Eye. 70%of his body is replaced with black almost bug like carapace (half his face) the replacements are as strong as flesh but cant merge with power armour making him whole but unable to fight with the host.(many a dark curse has been spoken by him over this turn of events)

Eshmunazar is lucky, he was never the best Astartes on the ground, his forte was space combat, thinking in more dimensions than a sane man can. So when the host got the Verbum, Castor raised him to commander. Eshmunazar is proud of this and runs a clean and crisp ship. This is his way back to the brotherhood of the host and he wont let anyone get in the way of it.