GR translation: ready only to assume him

[Mike Jing]

V142.14-20, P144.32-38   Oh yes once you know, he did believe in a Minotaur
waiting for him: used to dream himself rushing into the last room,
burnished sword at the ready, screaming like a Commando, letting it all out
at last—some true marvelous peaking of life inside him for the firstand
last time, as the face turned his way, ancient, weary, seeing none of
Pointsman’s humanity, ready only to assume him in another long-routinized
nudge of horn, flip of hoof

What does "assume" mean here?