Sun Titan + Sakashima the Impostor + Loyal Retainers + Phyrexian Altar

Sun Titan

Sakashima the Impostor

Loyal Retainers

Phyrexian Altar

How it works

1. Cast Sun Titan.
2. When Sun Titan enters the battlefield you may, return Loyal Retainers to the battlefield.
3. Activate Loyal Retainers, targeting Sakashima the Impostor.
4. Have Sakashima the Impostor enter as a copy of Sun Titan.
5. With Sakashima's enter the battlefield ability, return Loyal Retainers to the battlefield.
6. Sacrifice Sakashima to Phyrexian Altar.
7. Activate Loyal Retainers, targeting Sakashima the Impostor.
8. Repeat.

This brilliant loop turns a recursive legendary copy engine into an infinite mana and trigger machine. With Phyrexian Altar providing a sacrifice outlet that converts every iteration into any color of mana, Loyal Retainers acts as the ultimate graveyard-to-field bridge for our key threat. When you cast Sun Titan, it fetches Loyal Retainers, which in turn resurrects Sakashima the Impostor. By having Sakashima enter the battlefield as a copy of Sun Titan, its own clone trigger immediately pulls Loyal Retainers right back out of the graveyard to sustain the loop indefinitely.