How can you create a combo with Rootha, Mercurial Artist, Fork?
user
[START OF COMBO]This combo can be formed with Rootha, Mercurial Artist, Fork

Color identity: UR
Mana cost: {2}{R}{R}
Steps:
  1. Cast an instant or sorcery spell, or wait for an opponent to cast one.
  2. Holding priority, cast Fork by paying {R}{R}, targeting the spell.
  3. Activate Rootha by paying {2} and returning it to your hand, copying Fork, with the copy targeting the original Fork.
  4. Resolve the copy of Fork, copying Fork, targeting the original Fork.
  5. Repeat step 4.[END OF COMBO STEPS]

Result:
  - Infinite magecraft triggers[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Rootha, Mercurial Artist must be on the battlefield
  - Fork must be in your hand
[END OF COMBO PREREQUISITES]
assistant