Anticlimatic Escape (1)
As Samiel was bombarding the military fortress of the bats, vampires were panicking inside because they realized that they had fallen into some kind of trap. The orks that lurked around were just a pretext to lure out their forces where.
Unfortunately for the Vampires, they figured out this too late when the trap was already in a full go and there was already no return from this point.
They were all ambushed and killed to the last man, inflicting great losses on the vampires in the Bone Mountains. It was a very efficient trap that cut their numbers by half in one swoop and now, they were attacking their headquarters too...
And when someone started bombarding their headquarters with intense magic spells, literarily spamming 5th Level Spells like they were nothing, not to mention that each spell was highly destructive.