Disa the Restless + Altar of Dementia + Arashin Sovereign + Maskwood Nexus

Disa the Restless

Altar of Dementia

Arashin Sovereign

Maskwood Nexus

How it works

1. Activate Altar of Dementia by sacrificing Arashin Sovereign.
2. When Arashin Sovereign dies, it triggers, putting itself from your graveyard onto the top of your library.
3. Resolve the Altar of Dementia ability, causing you to mill cards equal to Arashin Sovereign's power, which will cause you to mill Arashin Sovereign.
4. As Arashin Sovereign is a Lhurgoyf due to Maskwood Nexus, Disa's first ability triggers, returning Arashin Sovereign from your graveyard to the battlefield.
5. Repeat.