He had been tasked with guarding it: the Aperture, the chrysalis buried beyond. Only he, aside from Master Vargas, knew where it had been buried; and it was in one of his slow patrols between the mouth of Draco and the stone itself that he'd seen the creature approach.

His stride stopped just outside the Aperture.

He noted its crawling. The bleeding. The Oil. A first impulse for some might have been to offer aid; but the Sentinel had no aid to give, and he was, indeed, a sentinel. Instead he hid himself, pulling back into the dark, and watching to see if anything might be chasing the little cat. Something greater, some enemy he might actually have to deal with; something he'd want the first strike on, instead of being caught kneeling before its victim in the open.

Nothing came.

When he returned to Purity, following its trail of blood, he found its gemstone taking it. It was a pretty stone, the Sentinel reflected, and simply stood staring down at it for awhile: a deep, rich blue, one whose glimmering perfection eclipsed the strangely macabre scene within.

Halberd-butt was extended down, to prod at the stone once or twice; it seemed pointless to ask why the cat was here, now. Given that it was nearly dead.

Instead he resolved to inform the Master that someone had crawled in, and returned to their stone; that this someone was touched by Oil. Maybe it would be someone he'd be interested in.

He seemed to like cats, after all.