Adarkar Valkyrie (MMA 1)

Snow Creature — Angel • Mana cost: {4}{W}{W} • Modern Masters • Rare

Flying, vigilance
{T}: When target creature other than this creature dies this turn, return that card to the battlefield under your control.

She doesn't escort the dead to the afterlife, but instead raises them to fight and die again.

Illustrated by Jeremy Jarvis.