Altar of Dementia + Thran Vigil + Thunderblust

Altar of Dementia

Thran Vigil

Thunderblust

How it works

1. Activate Altar of Dementia by sacrificing Thunderblust.
2. When Thunderblust dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. Thran Vigil triggers, putting a +1/+1 counter on Thunderblust.
4. Resolve the Altar of Dementia ability.
5. Repeat.

This crafty loop turns Thunderblust's own resurrection mechanics into an endless mill engine by exploiting the interaction between persist and counter placement. When you feed Thunderblust to Altar of Dementia, its persist trigger brings it straight back to the battlefield bearing a -1/-1 counter, which simultaneously satisfies Thran Vigil as it leaves the graveyard. Thran Vigil immediately responds by placing a +1/+1 counter on Thunderblust, whose state-based actions cause the opposing +1/+1 and -1/+1 counters to annihilate each other. Because Thunderblust is once again free of counters, it can be sacrificed to Altar of Dementia all over again to repeat the entire cycle for infinite milling and death triggers.