Ritual of Fasting

Whenever a vampire you control attacks,
sacrifice a Blood token or place a thirst counter
on it. Vampires you control gain -1/-1 for each
thirst counter on them.

Remove 15 thirst counters from vampires you
control: Create Edheljorn, a legendary 15/15
black Vampire Demon God creature token
with indestructible, hexproof, and lifelink.