Zoanthrope

When Zoanthrope enters the battlefield, tap all creatures target opponent controls. If a artifact creature was tapped this way, it doesn't untap
during its controller's next untap step.
{5}, Sacrifice Zoanthrope: Destroy target creature.
Despite their power, Zoanthropes sometimes seem to
be victims of their own massive energy reserves and
there have been numerous reports of Zoanthropes
"burning out" in battle.