Nevermind is a uncommon Instant — Arcane card from Unknown Event (UNK), collector number UR11a.
(Spells without mana costs can't be played) When this spell resolves, discard a card. Then draw a card. Splice onto Anything {1}{R} (As you cast a spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effect to that spell.)