Cast Through Time + Venser, Shaper Savant + Sanctum of Eternity + Time Warp

Cast Through Time

Venser, Shaper Savant

Sanctum of Eternity

Time Warp

How it works

1. Cast Time Warp by paying 3, granting you an extra turn after this one and exiling it due to rebound.
2. At the beginning of your next upkeep, rebound triggers, causing you to cast the exiled spell without paying its mana cost.
3. Activate Sanctum of Eternity by tapping it and paying 2, returning Venser from the battlefield to your hand.
4. Cast Venser by paying 2, returning the extra turn spell to your hand.
5. Repeat each turn.