Reiterate + Desperate Ritual + Bonus Round

Steps

1. Cast Bonus Round by paying {1}{R}{R}.
2. Cast Desperate Ritual by paying {1}{R}.
3. Bonus Round triggers, creating a copy of Desperate Ritual.
4. Resolve the Desperate Ritual copy, adding {R}{R}{R}.
5. Holding priority, cast Reiterate with buyback by paying {4}{R}{R}{R}, creating a copy of Desperate Ritual.
6. Bonus Round triggers, creating a copy of Reiterate.
7. Resolve the Reiterate copy, creating a copy of Desperate Ritual.
8. Resolve the second Desperate Ritual copy, adding {R}{R}{R}.
9. Resolve the first copy of Desperate Ritual, adding {R}{R}{R}.
10. Repeat from step 5.