Desperate Ritual is a uncommon Instant — Arcane card from Duel Decks: Mind vs. Might (DDS), collector number 14. Current market price: $6.45, TCGplayer market prices via Scryfall.
Add {R}{R}{R}. Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)