Cave of the Frost Dragon is a rare Land card from Adventures in the Forgotten Realms Promos (PAFR), collector number 253p. Current market price: $0.67 (foil $1.54), TCGplayer market prices via Scryfall.
If you control two or more other lands, this land enters tapped. {T}: Add {W}. {4}{W}: This land becomes a 3/4 white Dragon creature with flying until end of turn. It's still a land.
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