How can you create a combo with Gravecrawler, Rooftop Storm, Grimgrin, Corpse-Born?
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[START OF COMBO]This combo can be formed with Gravecrawler, Rooftop Storm, Grimgrin, Corpse-Born

Color identity: UB
Mana cost: 
Steps:
  1. Activate Grimgrin's ability by sacrificing Gravecrawler, untapping Grimgrin and putting a +1/+1 counter on Grimgrin.
  2. Cast Gravecrawler from your graveyard by paying {0}.
  3. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite +1/+1 counters on Grimgrin
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite sacrifice triggers
  - Infinite storm count[END OF COMBO RESULT][END OF COMBO]

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