Primal Prayers is a rare Enchantment card from Modern Horizons 3 (MH3), collector number 339. Current market price: $0.45 (foil $1.57), TCGplayer market prices via Scryfall.
When this enchantment enters, you get {E}{E} (two energy counters). You may cast creature spells with mana value 3 or less by paying {E} rather than paying their mana costs. If you cast a spell this way, you may cast it as though it had flash.