Roiling Vortex is a rare Enchantment card from Zendikar Rising Promos (PZNR), collector number 156p. Current market price: $3.22 (foil $3.24), TCGplayer market prices via Scryfall.
At the beginning of each player's upkeep, this enchantment deals 1 damage to them. Whenever a player casts a spell, if no mana was spent to cast that spell, this enchantment deals 5 damage to that player. {R}: Your opponents can't gain life this turn.