Pyromancer's Goggles + Reverberate

Prerequisites

You have an additional instant or sorcery card in hand.

Steps

1. Cast any instant or sorcery by paying its mana cost.
2. Holding priority, activate Pyromancer's Goggles by tapping it, adding {R}.
3. Cast Reverberate by paying its mana cost, targeting the instant or sorcery cast in step 1.
4. Pyromancer's Goggles triggers, copying Reverberate, with the copy targeting the original Reverberate.
5. Resolve the copy of Reverberate, creating a copy of Reverberate targeting the original Reverberate.
6. Repeat step 5.