The X-Dimension is a darker version of the Netherworld with more challenging versions of the game's stages.
The X-Dimension is unlocked by having the player gain an Illegal Ticket from defeating pirates that arrive in floors 20+ of any legendary item world. A bill will be unlocked in the Classroom Assembly, and passing that bill and putting someone in the Tora no Ana club will unlock a new Samurai dimension guide.
There are 43 stages here, 24 that the player unlock via Illegal Tickets obtained from pirates. The rest are obtained by purchasing them from a Mystery Gate shop owned by a Reaper. There are 2 of these shops, one of which can be found in the earlier (<50) floors of the item world and the other is found in the later (>50) floors of the item world.
Many of these levels contain Geo Puzzles of extreme difficultly. Some of the worst Geo Effects come into play such as No Entry, No Throwing, Damage 100%, Reverse Damage and some exclusive Geo Effects such as Absolute Area (No Entry, No Lifting and Invincibility all in one) and Game Over (If any unit, even enemies, ends their turn on this panel, the player get an instant Game Over).
Clearing certain percents of X-Dimension stages grants access to certain Items:
|20% Completion||Naive Glasses||All attacks will hit.|
|40% Completion||Used Rag||Reduces the enemy's stats by 20% when attacked.|
|60% Completion||Stolen Shorts||Damage from geo effects and chains heals HP.|
|80% Completion||Chicken Hat||Null physical attacks on odd turns, null magical attacks on even turns.|
|100% Completion||Dark History||Normal attacks have a 20% chance of deathblow if target's HP is below 25%|
Clearing 25 of the 43 stages will unlock the Land of Carnage.