Double Vision + Venser, Shaper Savant + Panharmonicon + Time Warp

Double Vision

Venser, Shaper Savant

Panharmonicon

Time Warp

How it works

1. Cast Time Warp by paying 3.
2. Double Vision triggers, copying Time Warp.
3. Holding priority, cast Venser by paying 2.
4. When Venser enters the battlefield, it triggers twice, returning itself and the original Time Warp to your hand from the battlefield and stack respectively.
5. Resolve the copy of Time Warp, causing you to take an extra turn after this one.
6. Repeat each turn.

This looping extra-turn engine leverages Double Vision to multiply your spells right out of the gate, automatically generating a copy of Time Warp whenever you kick things off. To sustain the loop indefinitely, Panharmonicon doubles Venser, Shaper Savant's entry trigger, letting you neatly bounce both the original Time Warp back to your hand and Venser, Shaper Savant itself to your grip so you can recast it on the next turn. By looping these resources together, you permanently lock your opponents out of the game while taking infinite turns.