Ziatora's Proving Ground is a rare Land — Swamp Mountain Forest card from Streets of New Capenna (SNC), collector number 261. Current market price: $9.16 (foil $10.09), TCGplayer market prices via Scryfall.
({T}: Add {B}, {R}, or {G}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)