Mikaeus, the Unhallowed, Cryptic Trilobite, and Crovax, Ascendant Hero

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Cryptic Trilobite on the battlefield
• Crovax, Ascendant Hero on the battlefield

Steps

1. Activate Cryptic Trilobite by removing a +1/+1 counter from it, adding that can only be spent to activate abilities
2. Repeat step 1 until Cryptic Trilobite does not have any +1/+1 counters on it
3. Cryptic Trilobite dies as a state-based action due to having 0 toughness
4. Cryptic Trilobite's undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
5. Repeat

Results

• Infinite colorless mana that can only be spent to activate abilities
• Infinite death triggers
• Infinite ETB
• Infinite LTB