Ao, the Dawn Sky + Mortuary + Dack's Duplicate

Ao, the Dawn Sky

Mortuary

Dack's Duplicate

How it works

1. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter the battlefield as a copy of Ao.
2. Put Dack's Duplicate into your graveyard due to the legend rule.
3. When Dack's Duplicate dies, it and Mortuary trigger.
4. Resolve the Mortuary trigger, putting Dack's Duplicate from your graveyard onto the top of your library.
5. Resolve the Dack's Duplicate trigger, causing you to look at the top seven cards of your library and put Dack's Duplicate onto the battlefield as a copy of Ao.
6. Repeat from step 2.