Insatiable Hemophage

Mutate {2}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Deathtouch
Whenever this creature mutates, each opponent loses X life and you gain X life, where X is the number of times this creature has mutated.

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Ikoria: Lair of Behemoths

In a Two-Headed Giant game, Insatiable Hemophage’s last ability causes the opposing team to lose life equal to twice the value of X and you to gain X life.