Marco, Undying Slayer

Eminence — As long as Marco, Undying Slayer is in the command zone or on the battlefield, whenever Jacopo, Beacon of Hope dies, you may pay {w/b}{w/b}. If you do, return Jacopo to the battlefield transformed and move Marco, Undying Slayer to the command zone.

Blood Bond — Whenever another creature you control dies, put a +1/+1 counter on Marco, Undying Slayer.

Marco, Undying Slayer cannot be cast if Jacopo, Beacon of Hope is trasformed.