The Mirror Sanctum

*"The Mirror Dimension, ever present but undetected. The real world isn't affected by what happens here. We use the Mirror Dimension to train, surveil, and sometimes to contain threats."*
―Ancient One to Doctor Strange[src]
The **Mirror Dimension** is a parallel dimension that allows the user to practice their magical abilities and fight their enemies without the public's knowledge. Those who use the power of the Dark Dimension have a stronger control over space and matter than they usually would, to the point of being able to fold and warp space in reality.

## Overview

The Mirror Dimension allows an advanced sorcerer to train more advanced and dangerous spells without adversely affecting the real world, keep an eye on threats without being noticed, and a prison for those without a Sling Ring. The final usage is paramount that a prisoner is locked without a Sling Ring as it is the only means to escape. However, the realm is shown to be accessible without the use of the Sling Ring, which allowed the likes of the Ancient One and Doctor Strange to transport themselves and others into the dimension, though a Sling Ring was ultimately required to leave it.

In addition, the Mirror Dimension can be used in combat by a sorcerer with the knowledge and skill needed to perform it liberally by manifesting a gateway to it to absorb attacks and then sending the manifestation at the enemy to trap them at the Mirror Dimension, but these Mirror Dimension gateways can seemingly be destroyed when enough power is directed at them, as Thanos was able to use the Power Stone to destroy a gateway that was sent towards him by Doctor Strange. In addition if two sections of the Mirror Dimension converge, it will cause a disruption that will temporarily destabilize the entire dimension; as shown when Spider-Man and Doctor Strange fought inside it.

## History

### Theft of the Book of Cagliostro

After stealing a page from the Book of Cagliostro, Kaecilius and his followers, the Zealots, escaped through a portal to London with the Ancient One in pursuit. The Ancient One proceeded to send them to the Mirror Dimension to remove the danger they presented to the real world. In the resulting battle, several Zealots were killed by the warped landscape but Kaecilius managed to open a portal and escape with the page. The Ancient One exited the Mirror Dimension and reentered London.

### Training Doctor Strange

*"You're advancing quickly with your sorcery skills. You need a safe space to practice your spells."*
―Ancient One to Doctor Strange[src]
While training new recruit Doctor Strange, the Ancient One brought him to the Mirror Dimension and explained its unique properties.

### Battle of the Mirror Dimension

*"The Mirror Dimension. You can't affect the real world in here. Who's laughing now, asshole?""I am."*
―Doctor Strange and Kaecilius[src]
In order to protect the New York Sanctum from getting destroyed by Kaecilius and the Zealots, Doctor Strange trapped all of them inside the Mirror Dimension. However, Karl Mordo informed Strange that the Zealots' connection to the Dark Dimension made them even stronger in the Mirror Dimension. Realizing that their plan backfired, Mordo and Strange tried to escape. Strange stole Kaecilius's Sling Ring and tried to conjure a portal only for Kaecilius to distort gravity and make him lose focus. They were then purused through New York City with the landscape twisting to the point that it was unrecognizable. Strange was aided by the Cloak of Levitation in the fight against them. Using the changing landscape to his advantage, Kaecilius cornered Strange and reclaimed his Sling Ring.

The Ancient One then appeared and used her powers to create a battle arena out of subway station walls. Kaecilus signaled his Zealots to attack her, and as she was occupied, he conjured a Space Shard and stabbed her fatally. He then proceeded to throw her out of the Dimension.

### Battle of Titan

In 2018, while on the planet Titan, Doctor Strange opened a gateway to the Mirror Dimension to protect himself against an energy blast from the Power Stone unleashed by Thanos and then sent the gateway at Thanos in order to trap him in the Dimension only for Thanos to shatter the dimensional gate via the Power Stone before using the Space Stone to collapse the remnants into a destructive black hole that he threw at Strange.

### Fractured Spell

*"Is that an Archimedean Spiral? The Mirror Dimension is just geometry? You're great at geometry! You could do geometry!"*
―Spider-Man[src]
*To be added*

### Alternate Universes

#### Strange Supreme

After Stephen Strange resurrected Christine Palmer, his universe began to collapse and Strange struggled to hold it back, Strange begged The Watcher, whom he had noticed earlier, to help him fix back his universe and punish him instead, but the Watcher refused, stating that "meddling with time and events only leads to more destruction", shortly after leaving, Strange's universe entirely collapsed, saved for a reality bubble composed of the remains of the Mirror Dimension held together by Strange's magic, as Palmer faded away in his arms questioning what he had done, Strange sobbed and apologized, left alone as the last survivor of his home universe.

#### Visited by The Watcher

The Watcher later ended up in Strange's pocket dimension after escaping his battle against Ultron. With the Multiverse in peril, the Watcher reluctantly decided to break his non-interference oath to request Strange's assistance against Ultron.

Strange later returned to the Mirror Dimension with the Watcher. While holding a miniaturized pocket dimension containing Killmonger, Arnim Zola and the Infinity Stones, Strange remarked that the Watcher had foreseen everything in the Guardians of the Multiverse's battle, from the failed Infinity Crusher to Killmonger's betrayal. The Watcher added he also foresaw Strange sacrificing himself to guard the imprisoned villains to keep them from escaping, a task Strange agreed to undertake.