Elbrus, the Binding Blade // Withengar Unbound

Legendary Artifact — Equipment

Equipped creature gets +1/+0.

When equipped creature deals combat damage to a player, unattach Elbrus, then transform it.

Equip {1}

Legendary Creature — Demon

Flying, intimidate, trample (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Whenever a player loses the game, put thirteen +1/+1 counters on Withengar Unbound.