Elvenking's Halls is a common Land card from The Hobbit (HOB), collector number 182. Current market price: $0.16 (foil $0.18), TCGplayer market prices via Scryfall.
This land enters tapped. {T}: Add {G} or {U}. {2}{G}{U}, {T}, Sacrifice this land: Put two +1/+1 counters on target Elf you control. Activate only as a sorcery.