Furgul, Quag Nurturer (YMKM-023) [Alchemy: Murders at Karlov Manor ]

At the beginning of your end step, conjure a card named Slimy Dualleech onto the battlefield if you control no Leeches. Otherwise, put a +1/+1 counter on each Leech you control.
, Sacrifice a creature: Add an amount of equal to the sacrificed creature's power.