Primal Prayers (MH3) from Modern Horizons 3, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Yeong-Hao Han
• Card Text:
  When Primal Prayers enters the battlefield, you get EE (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.