codex seraphinianus
simply find the weakness
hold [_] longer for more power
climb your way skyward
When they first meet, Trevor distrusts Dietrich for being a Devil Forgemaster, and a battle ensues. Trevor then defeats Dietrich and mocks him for being a weak ally of Dracula. Afterwards, Trevor becomes a cautious ally, working behind the scenes. He isn't seen again until much later in the game, in the Aiolon Ruins.
LOST
all is not lost.