Shaddeus, the Dealmaker

Indestructible, vigilance.
Shaddeus can't attack or block unless there are
6 or more tithe counters among permanents.
Whenever a creature with a tithe counter on it
dies, its owner may pay {x} where X is twice the
number of tithe counters it had. If they don't,
exile it and create a token that's a copy of it.
{1}{w/b}{w/b}, {t}: Put a tithe counter on target
creature you don't control, and a tithe counter
on target creature you do control.