Skemfar Shadowsage is a uncommon Creature — Elf Cleric card from Foundations Jumpstart (J25), collector number 489. Current market price: $0.29, TCGplayer market prices via Scryfall.
When this creature enters, choose one — • Each opponent loses X life, where X is the greatest number of creatures you control that have a creature type in common. • You gain X life, where X is the greatest number of creatures you control that have a creature type in common.