Rootha, Mercurial Artist, and Twincast

Prerequisites

• Rootha, Mercurial Artist on the battlefield
• Twincast in hand
• available

Steps

1. Cast an instant or sorcery spell, or wait for an opponent to cast one
2. Holding priority, cast Twincast by paying , targeting the spell
3. Activate Rootha by paying and returning it to your hand, copying Twincast, with the copy targeting the original Twincast
4. Resolve the copy of Twincast, copying Twincast, targeting the original Twincast
5. Repeat step 4

Results

• Infinite magecraft triggers