Ancient's Offering

Split Second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Scry X, where X is equal to 1 plus the number of spells on the stack.
Splice onto Arcane {1}{u} (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.)