Mikaeus, the Unhallowed, Pith Driller, and Grinding Station

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Pith Driller on the battlefield
• Grinding Station on the battlefield
• Pith Driller does not have a +1/+1 counter on it

Steps

1. Activate Grinding Station by tapping it and sacrifiicing Pith Driller
2. When Pith Driller dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
3. When Pith Driller enters the battlefield, it and Grinding Station trigger
4. Resolve the Pith Driller trigger, putting a -1/-1 counter on it
5. Resolve the Grinding Station trigger, untapping it
6. Resolve the Grinding Station ability from step 1, causing target player to mill three cards
7. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite mill
• Infinite self-mill