Extravagant Replication + Timeless Witness + Notorious Throng

Extravagant Replication

Timeless Witness

Notorious Throng

How it works

1. Deal combat damage to an opponent using a Rogue
2. Cast Notorious Throng for its prowl cost by paying 5, causing you to take an extra turn after this one.
3. Move to your next turn.
4. At the beginning of your upkeep, Extravagant Replication triggers, creating a token copy of Timeless Witness.
5. When the Timeless Witness token enters the battlefield, it triggers, returning Notorious Throng from your graveyard to your hand.
6. Repeat.

This delightful engine feeds on itself indefinitely by turning your upkeep step into a perpetual motion machine of extra turns and recursive value. It all begins when you cast Notorious Throng for its prowl cost, dealing combat damage with a Rogue to take an extra turn and binning the sorcery in the process. Once you arrive at the start of that bonus turn, Extravagant Replication triggers to mint a fresh copy of Timeless Witness, whose enter-the-battlefield ability immediately plucks Notorious Throng right back out of your graveyard and into your hand. Because you can replay the spell and repeat this upkeep cloning cycle turn after turn, you secure infinite turns and a total game lock.