Mirrodin Besieged + Myr Retriever + Junk Diver + Krark-Clan Ironworks

Mirrodin Besieged

Myr Retriever

Junk Diver

Krark-Clan Ironworks

How it works

1. Activate Krark-Clan Ironworks by sacrificing Junk Diver, adding CC.
2. When Junk Diver dies, it triggers, returning Myr Retriever from your graveyard to your hand.
3. Cast Myr Retriever by paying 2.
4. Mirrodin Besieged triggers, creating a 1/1 Myr artifact creature token.
5. Activate Krark-Clan Ironworks twice by sacrificing the Myr and Myr Retriever, adding CCCC.
6. When Myr Retriever dies, it triggers, returning Junk Diver from your graveyard to your hand.
7. Cast Junk Diver by paying 3.
8. Mirrodin Besieged triggers, creating a 1/1 Myr artifact creature token.
9. Repeat.

This loop transforms a recursive graveyard engine into an unstoppable cascade of value by leveraging Krark-Clan Ironworks as both the mana source and the sacrifice outlet. As Junk Diver and Myr Retriever endlessly trade places between your graveyard and hand, each iteration generates a surplus of colorless mana and fuels Mirrodin Besieged, whose Phyrexian mode can outright win the game or whose Mirran mode floods the board with infinite Myr tokens.