One of the more mysterious planes of existence within Marvel lore is the Astral Plane. Full of mysterious ethereal beings, powerful energies, and dark, brooding enemies, this plane is often visited by many of Marvel's most powerful heroes.

Even though this strange realm has a long comic book history, very few comic fans actually know all of its deepest, darkest secrets. From its makeup to its many inhabitants, there is actually quite a bit to tell about the Astral Plane despite its incomprehensible nature. Here are 10 little known facts about Marvel's Astral Plane.

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10 Made Of Ectoplasm

Ectoplasm is a strange element. Often thought to be a sign of supernatural presence, ectoplasm has made its way into many mythologies outside of Marvel. Within the Marvel universe, this material still has its traditional origins, having connections to the dead and the spiritual.

The Astral Plane is a somewhat purely spiritual world. Filled with disembodied consciousnesses and mysterious sentient energies, there's no wonder that the whole place is made up of ectoplasm. While not known for housing ghosts, the Astral Plane still manages to be quite the spooky place.

9 Alternate Dimension

Hulk Doctor Strange astral projection

Although many people use the Astral Plane as a means of traversing the real world undetected, it is actually its own alternate dimension. As previously stated, certain beings are able to psychically enter this plane and move around in the world unseen. There are also vast spaces within this dimension that are totally separated from our world.

These spaces have been used time and again to imprison dangerous enemies that have powerful psychic minds. Any visit to this dimension must be made with extreme caution given this fact.

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8 Telepaths

Ultimate Professor X Xavier

Among the people able to access the Astral Plane are telepaths. Telepaths can project their consciousness outward from their body, allowing them to traverse the world in a nearly undetectable form from which they can scout different areas or spy on hidden enemies.

An ability only very powerful telepaths are capable of, heroes such as Professor X, Emma Frost, and Jean Grey have been known to use this ability for a variety of purposes. Professor X in particular can quite often be found astral projecting.

7 Magic-Users

In addition to psychics, certain magic users are also capable of entering this mysterious realm. Using certain spells and incantations, these magic users can project their minds in much the same way that a telepath would.

Doctor Strange is notorious for using this ability. In fact, astral projection was first shown on the pages of a Doctor Strange comic book. It is quite likely that the good doctor uses this ability even more than Professor Xavier does.

Related: All Of Doctor Strange’s Powers & Abilities, Ranked

6 Duels of the Mind

Psylocke vs the Shadow King in X-Treme X-Men

This alternate dimension is actually used as somewhat of a battleground for psychics. Both Doctor Strange and Professor X have had many significant battles within the Astral Plane.

Essentially, the stronger one's mind is the stronger his astral projection will be in combat. Each combatant is able to conjure all sorts of energies and weapons that appear to physically manifest in this mindscape. In reality, however, this is all simply a representation of two or more powerful minds contending with one another.

5 Proteus

Kevin MacTaggert in his Proteus form

Also known as Mutant X, Proteus is actually Kevin MacTaggert the son of long-time X-Men ally Moira MacTaggert. One of the deadliest mutants to ever live, Proteus was locked up by his mother in order to keep the world safe.

Eventually breaking out, Proteus became one of the X-Men's most formidable opponents. After discovering the Astral Plane, Proteus attempted to use his vast powers to merge it with reality. This created a chaotic reality, bending itself into the gestalt of whatever the nearest peoples' minds could think of. Fortunately enough, he was defeated again by the X-Men.

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4 The Shadow King

One of the X-Men's most powerful psychic enemies, the Shadow King has long plagued the mutant team. Over the years he has become the psychic arch-nemesis of Professor Xavier himself.

The two powerful telepaths have battled many times on the Astral Plane, each combatant coming out victorious on different occasions. After their first encounter, Professor Xavier successfully defeated the evil mutant and stranded him on the Astral Plane. From there, the Shadow King has staged many telepathic attacks on various heroes and continues to do so.

3 Mummudrai

Baby Xavier attacking baby Cassandra Nova

The mummudrai are a race of psionic beings that exist within the Astral Plane. During the birth of every human being, the human must fight their respective negative-self, their mummudrai, before they are able to leave the womb. Most of these mummudrai die during this process. Others successfully devour their counterparts mind.

Mummundrai's that are killed don't truly die. Instead, their psychic form is brought to the Astral Plane where they exist in hopes of someday escaping. These beings are incredibly powerful, and have been used by the Shi'ar Empire as weapons of war to be unleashed upon their enemies.

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2 Cassandra Nova

Cassandra Nova prepares to attack

Professor Xavier had his own mummundrai at the time of his birth. Later known as Cassandra Nova, this psychic entity would go on to create her own physical body and become one of the X-Men's most horrible enemies.

Of the many dark acts she has committed, the most notable was her massacre of the mutants of Genosha. After taking command of an army of Sentinels, this X-Men villain used the mutant-hunting robots to invade Genosha and murder millions of innocent mutants. The total body count was around sixteen million.

1 Borders Nightmare's Domain

One of the more interesting things about this realm is its location. The Astral Plane is somewhat within the real world, and yet it is also completely separate. There are many other dimensions that have very similar qualities. One of them, the Dream Dimension, borders the Astral Plane.

Split into many different parts, the section of the Dream Dimension that borders the Astral Plane is actually the Nightmare World. Ruled over by the terrifying enemy of Doctor Strange known as Nightmare, this dimension is one most people hope to avoid. One of the many dangers of the Astral Plane is that the unsuspecting traveler may stumble upon one of the most terrifying villains in Marvel comics.

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