Ozox, the Clattering King + Phyrexian Altar + Sek'Kuar, Deathkeeper

Ozox, the Clattering King

Phyrexian Altar

Sek'Kuar, Deathkeeper

How it works

1. Activate Phyrexian Altar by sacrificing Ozox, adding 1.
2. When Ozox dies, it and Sek'Kuar trigger.
3. Resolve the Ozox trigger, creating a legendary 2/1 Jumblebones creature token.
4. Resolve the Sek'Kuar trigger, creating a creature token.
5. Activate Phyrexian Altar twice by sacrificing Jumblebones and the other creature token, adding 1.
6. When Jumblebones dies, it triggers, returning Ozox from your graveyard to your hand.
7. Cast Ozox by paying 2.
8. Repeat.