Mikaeus, the Unhallowed + Phyrexian Altar + The Reaper, King No More
Produces: Infinite ETB, Infinite LTB, Infinite colored mana, Infinite death triggers, Infinite sacrifice triggers, Infinite -1/-1 counters, Infinite recursion of non-Human creatures you control
- Mikaeus, the Unhallowed
- Phyrexian Altar
- The Reaper, King No More
- Color identity
- BRG
Steps
- Activate Phyrexian Altar by sacrificing The Reaper.
- When The Reaper dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
- When The Reaper enters the battlefield, it triggers, putting a -1/-1 counter on it.
- Repeat.