Cast Time Warp by paying {3}{U}{U}, causing you to take an extra turn after this one.
Activate Roon by paying {2} and tapping it, exiling Eternal Witness until the beginning of your end step.
At the beginning of your end step, Roon triggers, returning Eternal Witness from exile to the battlefield.
Eternal Witness enters the battlefield, putting Time Warp into your hand from your graveyard.
Repeat each turn.

Infinite turns

Lock

Roon of the Hidden Realm

Eternal Witness

Time Warp

Cast Time Warp by paying {3}{U}{U}, causing you to take an extra turn after this one.
Activate Roon by paying {2} and tapping it, exiling Archaeomancer until the beginning of your end step.
At the beginning of your end step, Roon triggers, returning Archaeomancer from exile to the battlefield.
Archaeomancer enters the battlefield, putting Time Warp into your hand from your graveyard.
Repeat each turn.

Archaeomancer

Cast Temporal Manipulation by paying {3}{U}{U}, causing you to take an extra turn after this one.
Activate Roon by paying {2} and tapping it, exiling Eternal Witness until the beginning of your end step.
At the beginning of your end step, Roon triggers, returning Eternal Witness from exile to the battlefield.
Eternal Witness enters the battlefield, putting Temporal Manipulation into your hand from your graveyard.
Repeat each turn.

Temporal Manipulation

Cast Temporal Manipulation by paying {3}{U}{U}, causing you to take an extra turn after this one.
Activate Roon by paying {2} and tapping it, exiling Archaeomancer until the beginning of your end step.
At the beginning of your end step, Roon triggers, returning Archaeomancer from exile to the battlefield.
Archaeomancer enters the battlefield, putting Temporal Manipulation into your hand from your graveyard.
Repeat each turn.

Cast Walk the Aeons by paying {4}{U}{U}, causing you to take an extra turn after this one.
Activate Roon by paying {2} and tapping it, exiling Eternal Witness until the beginning of your end step.
At the beginning of your end step, Roon triggers, returning Eternal Witness from exile to the battlefield.
Eternal Witness enters the battlefield, putting Walk the Aeons into your hand from your graveyard.
Repeat each turn.

Walk the Aeons

Cast Walk the Aeons by paying {4}{U}{U}, causing you to take an extra turn after this one.
Activate Roon by paying {2} and tapping it, exiling Archaeomancer until the beginning of your end step.
At the beginning of your end step, Roon triggers, returning Archaeomancer from exile to the battlefield.
Archaeomancer enters the battlefield, putting Walk the Aeons into your hand from your graveyard.
Repeat each turn.

Blink Wormfang Manta using Roon of the Hidden Realm. Wormfang Manta's first ability won't trigger due to Hushwing Gryff.
Wormfang Manta's second ability triggers, causing you to take an extra turn after this one.
Repeat each turn.

Wormfang Manta

Hushwing Gryff

Activate Timestream Navigator by paying {2}{U}{U}, tapping it and putting it from the battlefield onto the bottom of your library, causing you to take an extra turn after this one.
Blink Recruiter of the Guard using Roon of the Hidden Realm.
When Recruiter of the Guard enters, it triggers, searching your library for Timestream Navigator and putting it into your hand.
Cast Timestream Navigator by paying {1}{U}.
Repeat each turn.

Timestream Navigator

Recruiter of the Guard

Deal combat damage using Medomai, triggering its ability, causing you to take an extra turn after this one.
Cast The Wondrous Wasp by paying {1}{U}.
When The Wondrous Wasp enters, it triggers, tapping Medomai and causing it to lose all its abilities until The Wondrous Wasp leaves the battlefield.
Move to your next turn.
Declare Medomai as an attacker.
Holding priority, activate Roon of the Hidden Realm by paying {2} and tapping it, exiling The Wondrous Wasp until your end step. This will also cause Medomai to regain its abilities.
Deal combat damage using Medomai, triggering its ability, causing you to take an extra turn after this one.
At the beginning of your end step, Roon of the Hidden Realm triggers, returning The Wondrous Wasp from exile to the battlefield.
Repeat from step 3.

Combos with "Roon of the Hidden Realm"