Case of the Shattered Pact is a uncommon Enchantment — Case card from Murders at Karlov Manor (MKM), collector number 1. Current market price: $0.26 (foil $0.31), TCGplayer market prices via Scryfall.
When this Case enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle. To solve — There are five colors among permanents you control. (If unsolved, solve at the beginning of your end step.) Solved — At the beginning of combat on your turn, target creature you control gains flying, double strike, and vigilance until end of turn.