Doom's Time Platform + Clockspinning + Time Warp

Doom's Time Platform

Clockspinning

Time Warp

How it works

1. Cast Time Warp by paying its mana cost, causing you to take an extra turn after this one.
2. Declare any creature as an attacker. When you do, Doom's Time Platform triggers, exiling Time Warp from your graveyard with two time counters on it.
3. Move to your next turn. At the beginning of your upkeep, Time Warp's suspend ability triggers, removing a time counter from it.
4. Cast Clockspinning with buyback by paying 3, removing a time counter from Time Warp and returning Clockspinning to your hand.
5. Time Warp's suspend ability triggers, causing you to cast it without paying its mana cost.
6. Resolve Time Warp, causing you to take an extra turn after this one.
7. Repeat from step 2 each turn.