Ozox, the Clattering King | Phyrexian Altar | Anax, Hardened in the Forge

Cards

Activate
Phyrexian Altar by sacrificing
Ozox, adding ({1} magic symbol) .
When
Ozox dies, it and
Anax trigger.
Resolve the
Ozox trigger, creating a legendary 2/1 Jumblebones creature token.
Resolve the
Anax trigger, creating a creature token.
Activate
Phyrexian Altar twice by sacrificing Jumblebones and the other creature token, adding ({1} magic symbol) ({B} magic symbol) .
When Jumblebones dies, it triggers, returning
Ozox from your graveyard to your hand.
Cast
Ozox by paying ({2} magic symbol) ({B} magic symbol) .
Repeat.