Ephemerate + Eternal Witness + Time Walk

Ephemerate

Eternal Witness

Time Walk

How it works

1. Cast Time Walk by paying its mana cost, causing you to take an extra turn after this one.
2. Cast Ephemerate by paying , blinking Eternal Witness and exiling Ephemerate.
3. When Eternal Witness enters, it triggers, returning Time Walk from your graveyard to your hand.
4. Move to your next turn. At the beginning of your upkeep, Ephemerate's rebound ability triggers, causing you to cast it from exile without paying its mana cost.
5. Resolve Ephemerate, blinking Eternal Witness.
6. When Eternal Witness enters, it triggers, returning Ephemerate from your graveyard to your hand.
7. Repeat.