Mortuary + Experimental Frenzy + Cathodion + Krark-Clan Ironworks

Mortuary

Experimental Frenzy

Cathodion

Krark-Clan Ironworks

How it works

1. Activate Krark-Clan Ironworks by sacrificing Cathodion, adding CC.
2. When Cathodion dies, it and Mortuary trigger.
3. Resolve the Cathodion trigger, adding CCC.
4. Resolve the Mortuary trigger, putting Cathodion on top of your library from your graveyard.
5. Cast Cathodion from the top of your library by paying 3.
6. Repeat.

This loop turns Cathodion and Krark-Clan Ironworks into a self-sustaining mana engine by leaning entirely on the graveyard and the top of your library. When you sacrifice Cathodion to Krark-Clan Ironworks, its death ability generates three colorless mana, which easily funds its own re-casting once Mortuary effortlessly redirects the dying automaton straight back to the top of your library. Meanwhile, Experimental Frenzy gives you the vital permission to cast Cathodion directly from that very top deck position, entirely bypassing the restriction that would normally stop you from playing from your hand.