Leonardo, Sewer Samurai + Solemnity + Krark-Clan Ironworks + Phyrexian Walker

Leonardo, Sewer Samurai

Solemnity

Krark-Clan Ironworks

Phyrexian Walker

How it works

1. Activate Krark-Clan Ironworks by sacrificing Phyrexian Walker.
2. Cast Phyrexian Walker from your graveyard by paying 0. It will not enter with a finality counter on it due to Solemnity.
3. Repeat.

This clever loop turns the unassuming Phyrexian Walker into an engine for infinite mana and triggers by leveraging Leonardo, Sewer Samurai's ability to recur creatures with power or toughness 1 or less straight from your graveyard. Solemnity is the linchpin that protects the loop from Leonardo's restriction, shutting down finality counters entirely so the Walker can be recast over and over again without being exiled upon death. Once the board is set, Krark-Clan Ironworks gladly accepts the repeated sacrifices to turn that endless parade of artifacts into an ocean of colorless mana, storm count, and triggers.