Mikaeus, the Unhallowed + Viscera Seer + Safehold Elite

Mikaeus, the Unhallowed

Viscera Seer

Safehold Elite

How it works

1. Activate Viscera Seer by sacrificing Safehold Elite.
2. When Safehold Elite dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. Resolve the Viscera Seer ability.
4. Activate Viscera Seer by sacrificing Safehold Elite.
5. When Safehold Elite dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
6. Resolve the Viscera Seer ability.
7. Repeat.

This clever loop relies on a clever mechanical interaction between two competing counter mechanics to achieve infinity. While Viscera Seer provides the free sacrifice outlet needed to repeatedly bin your creatures, the real engine is fueled by Mikaeus, the Unhallowed granting undying to your non-Humans. When Safehold Elite dies, its natural persist ability and the granted undying trigger simultaneously; because state-based actions cause +1/+1 and -1/-1 counters to annihilate each other upon entering the battlefield, alternating which counter type you choose to let resolve allows Safehold Elite to dodge death indefinitely.