Invoke Calamity + Narset's Reversal + Bonus Round

Invoke Calamity

Narset's Reversal

Bonus Round

How it works

1. Cast Bonus Round by paying 1.
2. Cast Invoke Calamity by paying 1.
3. Bonus Round triggers, copying Invoke Calamity.
4. Resolve the Invoke Calamity copy, casting Narset's Reversal without paying its mana cost.
5. Bonus Round triggers, copying Narset's Reversal targeting the original Narset's Reversal.
6. Resolve the copy of Narset's Reversal, copying Narset's Reversal targeting Invoke Calamity and returning the original Narset's Reversal to your hand.
7. Resolve the Narset's Reversal copy, copying Invoke Calamity and returning the original Invoke Calamity to your hand.
8. Resolve the Invoke Calamity copy, casting Invoke Calamity without paying its mana cost.
9. Repeat from step 3.
10. You may also choose to cast any number of instants or sorceries from your hand or graveyard with mana value 4 or less without paying their mana costs during step 4.

This clever spell-loop centers around Bonus Round, which supercharges your turn by copying every instant or sorcery you cast. By dropping Invoke Calamity, you abuse that copy mechanic to cast Narset's Reversal for free, which bounces the original Invoke Calamity and a copy of Narset's Reversal right back to your hand to perpetuate the cycle. Because Bonus Round triggers on every single cast, this loop generates infinite storm count and magecraft triggers while letting you repeatedly cast any other cheap spells from your hand or graveyard for zero mana.