Ao, the Dawn Sky, Mortuary, and Deceptive Frostkite

Prerequisites

• Ao, the Dawn Sky on the battlefield
• Mortuary on the battlefield
• Deceptive Frostkite in hand
• available

Steps

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

Results

• Infinite LTB
• Infinite ETB
• Infinite death triggers