Ray Harrison
The Third War

On the war-torn world of Armageddon, Chaplain Gavador of the Mortifactors leads the assault against the greenskin foes. As the world burns around him, he faces one of the mightiest of their kind.
Warhammer 40k
short

Also in:
The Third War For Armageddon
War For Armageddon: the Omnibus