Leonardo, Sewer Samurai + Solemnity + Phyrexian Altar

Leonardo, Sewer Samurai

Solemnity

Phyrexian Altar

How it works

1. Activate Phyrexian Altar by sacrificing the additional creature, adding one mana of any color.
2. Cast the creature from your graveyard by paying its mana cost. It will not enter with a finality counter on it due to Solemnity.
3. Repeat.

This loop turns your graveyard into an engine by letting Leonardo, Sewer Samurai leverage its ability to continuously recast small creatures. Solemnity is the linchpin that protects this recursion: by stopping counters from ever being put on creatures, it completely bypasses the finality counters that would normally exile your creatures when they leave play. Once the creature is back, Phyrexian Altar is ready to sacrifice it for mana to pay for the next cast, looping your threats endlessly for infinite storm count, sacrifices, and entry triggers.