Phyrexian Altar + Wormfang Drake + Hero of the Dunes

Phyrexian Altar

Wormfang Drake

Hero of the Dunes

How it works

1. Cast Wormfang Drake by paying its mana cost.
2. When Wormfang Drake enters, its first ability triggers, exiling Hero of the Dunes.
3. Activate Phyrexian Altar by sacrificing Wormfang Drake.
4. When Wormfang Drake dies, its second ability triggers, returning Hero of the Dunes from exile to the battlefield.
5. When Hero of the Dunes enters, it triggers, returning Wormfang Drake from your graveyard to the battlefield.
6. When Wormfang Drake enters, its first ability triggers, exiling Hero of the Dunes.
7. Repeat from step 3.