Odin, Helsblade

Menace
Esperfade {3}{b} (You may cast this spell as if it had
flash for its Epserfade cost. If you do, it returns to
its owner's hand at the beginning of their controller's
next end phase.)
When Odin, Helsblade enters the battlefield,
destroy target creature or planeswalker. You lose
life equal to that permanent's converted mana
cost.