Sigil of the New Dawn + Phyrexian Altar + Su-Chi + Planar Gate

Sigil of the New Dawn

Phyrexian Altar

Su-Chi

Planar Gate

How it works

1. Activate Phyrexian Altar by sacrificing Su-Chi, adding .
2. Su-Chi dies, triggering itself and Sigil of New Dawn.
3. Resolve the Su-Chi trigger, adding CCCC.
4. Resolve the Sigil of New Dawn trigger, causing you to pay 1 to return Su-Chi from your graveyard to your hand.
5. Cast Su-Chi by paying 1.
6. Repeat.

This clever loop relies on Su-Chi generating a surplus of mana whenever it hits the graveyard, turning its death into a net-positive engine. By feeding the construct into the Phyrexian Altar, you harvest the exact white mana needed to fund Sigil of the New Dawn's triggered ability, which effortlessly bounces the automaton straight back to your hand. Meanwhile, Planar Gate pulls heavy weight from the command zone or battlefield, discounting Su-Chi's casting cost so drastically that you are left with an endless cascade of colorless mana and sacrifice triggers with every single iteration.