How can you create a combo with Rootpath Purifier, Dryad Arbor, Earthcraft, Mesmeric Orb?
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[START OF COMBO]This combo can be formed with Rootpath Purifier, Dryad Arbor, Earthcraft, Mesmeric Orb

Color identity: G
Mana cost: 
Steps:
  1. Activate Earthcraft by tapping Dryad Arbor, untapping Dryad Arbor.
  2. Mesmeric Orb triggers, causing you to mill a card.
  3. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite self-mill[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
[END OF COMBO PREREQUISITES]
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