Kotis, Sibsig Champion + Altar of Dementia + Timeless Witness + Extra Turn Spell - GY on Resolution

Prerequisites

• You have enough mana available each turn to cast the extra turn spell and enough mana each extra turn to cast Timeless Witness.
• You have not cast a spell using Kotis
• Extra Turn Spell - GY on Resolution

Steps

1. 1Cast the extra turn spell by paying its mana cost, causing you to take an extra turn after this one.
2. 2Move to your extra turn.
3. 3Activate Altar of Dementia by sacrificing Timeless Witness, causing you to mill cards equal to Timeless Witness's power.
4. 4Cast Timeless Witness from your graveyard by paying its mana cost and exiling three other cards from your graveyard, ensuring not to exile the extra turn spell.
5. 5When Timeless Witness enters the battlefield, it triggers, returning the extra turn spell from your graveyard to your hand.
6. 6Repeat.

Effects

• Lock
• Near-infinite turns