Prismari, the Inspiration, and Reverberate

Prerequisites

• Prismari, the Inspiration on the battlefield
• Reverberate in hand
• available

Steps

1. Cast any other instant or sorcery by paying its mana cost
2. Holding priority, cast Reverberate by paying its mana cost, targeting the instant or sorcery cast in step 1
3. Reverberate's storm ability triggers, creating at least one copy of Reverberate targeting the original Reverberate
4. Resolve a copy of Reverberate, copying Reverberate targeting the original Reverberate
5. Repeat step 4

Results

• Infinite magecraft triggers