The multiverse is a concept that refers to the existence of infinite dimensions that comprise everything that is. Several dimensions exist in the multiverse. Some sorcerers, called Dimensional Shunters, can home in on the frequency of another reality and travel across the dimensional plane to this new world. Shunters however, can only shift dimension, not point in space so when they do "shunt" they will arrive in the new dimension at the exact coordinates they were just in. This is also very dangerous as most realities are uninhabitable. It is also possible to travel between worlds using an Isthmus Anchor, an object residing in one reality that belongs in another. When the Anchor is used alone, it acts similar to a Dimensional Shunter, transporting people and objects across the dimensional plane but to the same coordinates they were just in. When the anchor is used in conjunction with a Teleporter, it can open a portal to another point in space as well as another dimension, presumably by combining the Teleporter's ability to cross space in an instant with its own dimensional properties.
- Skulduggery Pleasant's Dimension: This dimension is where most of the events of the books take place.
- Mevolent's Dimension: In this dimension, Mevolent won the war, presumably because this dimension's version of Skulduggery Pleasant is still Lord Vile , unlike in the main dimension.
- The Faceless One's Original Dimension: The Ancients banished the Faceless Ones to this dimension millennia ago.
- The Faceless One's Current Dimension: After skipping around and destroying several dimensions, the Faceless Ones destroyed this dimension and were unable to travel any further. The dark gods still reside in this dimension.
- The Roarhaven Dimension: The city of Roarhaven was built in this dimension around the town in the main dimension and transported back to the main dimension during the War of the Sanctuaries.
- Mien's 40 dimensions: When Mien had Silas Nadir linked to his Gaol, the prison shifted between 40 dimensions in 5 seconds on a round trip, with only the front door anchored to the main dimension. Nothing is known about these 40 dimensions as they were never visited.
- Countless other destroyed dimensions: Before the Faceless Ones became trapped in their current dimension, they travelled to countless others destroying them entirely