Tarnation Vista is a mythic Land card from The Big Score Promos (PBIG), collector number 30p. Current market price: $0.81 (foil $1.02), TCGplayer market prices via Scryfall.
This land enters tapped. As it enters, choose a color. {T}: Add one mana of the chosen color. {1}, {T}: For each color among monocolored permanents you control, add one mana of that color.