Pattern of Rebirth + The Cauldron of Eternity + Iridescent Drake + Phyrexian Altar

Pattern of Rebirth

The Cauldron of Eternity

Iridescent Drake

Phyrexian Altar

How it works

1. Activate Phyrexian Altar by sacrificing Iridescent Drake, adding one mana of any color.
2. When Iridescent Drake dies, The Cauldron of Eternity and Pattern of Rebirth trigger.
3. Resolve the Cauldron of Eternity trigger, putting Iridescent Drake on the bottom of your library from your graveyard.
4. Resolve the Pattern of Rebirth trigger, putting Iridescent Drake from your library onto the battlefield.
5. When Iridescent Drake enters the battlefield, it triggers, returning Pattern of Rebirth from your graveyard to the battlefield attached to Iridescent Drake.
6. Repeat.

This clever loop uses Phyrexian Altar as a reliable sacrifice outlet that also fuels your mana supply. When you sacrifice Iridescent Drake, Pattern of Rebirth triggers to fetch another creature, but because The Cauldron of Eternity is quietly ordering your graveyard, the Drake gets tucked away where Pattern can immediately find it. Meanwhile, the Drake's own entry ability plucks Pattern of Rebirth right back out of the graveyard to re-enchant it, setting the stage for you to sacrifice the Drake to the Altar all over again.