Underworld Breach + Lion's Eye Diamond + Brain Freeze

Underworld Breach
Lion's Eye Diamond
Brain Freeze

Requires
Brain Freeze in your graveyard. All permanents on the battlefield. You have at least six other cards in hand and/or graveyard.
Steps
  1. Activate Lion's Eye Diamond by discarding your hand and sacrificing it, adding uuu
  2. Cast Lion's Eye Diamond from your graveyard for its escape cost by exiling three cards besides Brain Freeze from your graveyard
  3. Cast Brain Freeze from your graveyard for its escape cost by paying 1u and exiling three cards from your graveyard
  4. Brain Freeze's storm ability triggers, creating at least one copy of Brain Freeze targeting yourself, and any remaining copies targeting an opponent
  5. Resolve each Brain Freeze, causing yourself to mill six cards and, if applicable, an opponent to mill three cards for each Brain Freeze remaining
  6. Repeat
Results
Infinite self-mill. Near-infinite colored mana. Near-infinite storm count. Near-infinite magecraft triggers. Near-infinite mill.