The aco drew aggro at the beginning by unsummoning its own building, which has highest aggro priority for creeps. It's to mess with the creeping by having a target run away.

Letzzgo scrotumus maximus

Wait, so the new NE meta is actually the old old meta from 2016?! It's such nostalgia to see DH + Naga against ud Just wait, eventually we might get back into fiend meta for UD too