Doubling Cube + Karn, Silver Golem + Pemmin's Aura

Mana needed: {8}{U}{U}

U identity

Commander legal

The 3 combo pieces

How to execute it

  1. Activate Doubling Cube by paying {3} and tapping it, doubling your unspent mana.
  2. Activate Karn by paying {1}, causing Doubling Cube to become an artifact creature until end of turn.
  3. Cast Pemmin's Aura by paying {1}{U}{U}, enchanting Doubling Cube.
  4. Activate Pemmin's Aura's first ability by paying {U}, untapping Doubling Cube.
  5. Activate Doubling Cube by paying {3} and tapping it, doubling your unspent mana.
  6. Repeat from step 4.

What the combo produces