Siege of Atropos

The Siege of Atropos was the final battle of the Founding Conflict, which closed off the Dark Times as the Time Lords defeated the last forces resisting against their binding of time.

Conflict
The crisis was caused by two Ravagers, Swarm and Azure, usurping the Temple of Atropos and banishing the Mouri within.

On the promise of this being her final mission, the Fugitive Doctor was sent by the Division to restore the Temple and capture Swarm and Azure. She was accompanied by Karvanista and two other Division agents and infiltrated the Temple, where Swarm and Azure had setup thrones and were holding millions hostage within Passengers. The Doctor had the Mouri hide themselves inside a Passenger and gave them a signal to emerge whilst confronting the Ravagers herself. The Mouri retook their positions, restoring the Temple, whilst the Doctor's allies immoblised Swarm and Azure. (TV: Once, Upon Time)

Aftermath
Swarm was imprisoned on the Burnished Rage battleground in a containment chamber, with Division agents visiting every thousand years to check he was secure. Azure was suppressed within a human identity, Anna, and lived in Arctic Circle. (TV: The Halloween Apocalypse)

To protect them from Swarm and Azure, the Mouri were quantum locked against them. (TV: War of the Sontarans)

Legacy
Whilst in a time storm after taking a broken Mouri's place in the Temple, the Thirteenth Doctor fell into her time stream and experienced the events of the siege from her fugitive incarnation's perspective. (TV: Once, Upon Time)