Explosive Singularity - Soft Glow Showcase (NEO) from Kamigawa: Neon Dynasty, available at 401 Games Canada.

• Rarity: Mythic Rare
• Finish: Normal
• Artist: Ari
• Card Text:
  As an additional cost to cast this spell, you may tap any number of untapped creatures you control. This spell costs 1 less to cast for each creature tapped this way.
  Explosive Singularity deals 10 damage to any target.