Grim Monolith + Karn, Silver Golem + Training Grounds

U identity

Commander legal

The 3 combo pieces

What must be in place

Grim Monolith does not have summoning sickness.

How to execute it

  1. Activate Grim Monolith's first ability by tapping it, adding {C}{C}{C}.
  2. Activate Karn by paying {1}, causing Grim Monolith to become an artifact creature until end of turn.
  3. Activate Grim Monolith's last ability by paying {2}, untapping it.
  4. Repeat step 1 and 3.

What the combo produces