Sandwurm Convergence is a rare Enchantment card from Amonkhet (AKH), collector number 183. Current market price: $0.48 (foil $1.90), TCGplayer market prices via Scryfall.
Creatures with flying can't attack you or planeswalkers you control. At the beginning of your end step, create a 5/5 green Wurm creature token.