Mikaeus, the Unhallowed + Phyrexian Altar + Lingering Tormentor

Mikaeus, the Unhallowed

Phyrexian Altar

Lingering Tormentor

How it works

1. Activate Phyrexian Altar by sacrificing Lingering Tormentor.
2. When Lingering Tormentor dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. Activate Phyrexian Altar by sacrificing Lingering Tormentor.
4. When Lingering Tormentor dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
5. Repeat.

This clever loop exploits the opposing mechanics of persist and undying to achieve immortality for Lingering Tormentor. Thanks to Mikaeus, the Unhallowed granting undying to your non-Human creatures, the Tormentor returns with a +1/+1 counter the first time it dies. When you sacrifice it again to Phyrexian Altar, its native persist ability triggers instead, bringing it back with a -1/-1 counter which immediately cancels out the existing counter due to state-based actions. This alternating cycle of counters allows you to endlessly sacrifice Lingering Tormentor to Phyrexian Altar, generating an infinite supply of any color of mana alongside boundless entry, exit, and death triggers.