Ejosac, the Stalker

Whenever a creature enters the battlefield under an opponents control, choose one:
-Target creature you control becomes a 1/1 and gains deathtouch until end of turn.
-Sacrifice target creature under your control, Ejosac gains deathtouch and indestructible until end of turn.
"It is unclear where he came from, but we know
his only motive is death." - Thalia