A Great Door is an ornate set of double doors outlined in golden filigree. Great Doors may be used to travel between different Dark Worlds without entering the Light World, or to return from a Dark World to the Light World without closing the associated Dark Fountain.
While Great Doors appear only in Dark Worlds, they appear to have Light World counterparts. The Great Door in the Closet Dark World connects with Card Kingdom, while a locked door connects the Closet with the Unused Classroom in the Light World; the Great Door in TV World, which is in Kris's house, leads to the front lawn outside the house, corresponding with the open front door leading back to the Dark World inside; and Great Door in the church lobby's Dark World connects with the Dark World inside the Main Hall, while a locked door connects the two rooms in the Light World.
Main Story[]
Chapter 1[]
A Great Door can be found in the Closet Dark World by traveling to the right of the Training Area. Upon reaching it, Ralsei is surprised to find it open and implies to Kris that Lancer must have used it to come through from Card Kingdom. Passing through to the Field causes the Door to close behind the party, starting their first adventure.
The party can visit the Door after returning to Castle Town at the end of the chapter and examine it, revealing that it "may never open again." A Bloxer with three pairs of pants is located next to the door.
Chapter 2[]
The Great Door in the Closet Dark World is still closed, with its text unchanged. A lost Poppup, Tasque, and/or Maus may be found wandering there if they were recruited but Tasque Manager was not; if she was recruited, no lost animals appear at the Door even if they were recruited as well, but the Bloxxer has added a fourth pair of pants. If no animals are present and fewer than four cars were hit while driving with Queen, a tiny walking car appears instead.
The following two subsections contain spoilers for Chapters 3 and 4. If you wish to avoid spoilers, please refrain from reading the subsections.
Chapter 3[]
The Roaring Knight escapes TV World through a Great Door in a foggy area east of the Cold Place. Although unnamed, it is dimly visible through the fog as visually identical to the one in the Closet Dark World. When Kris and Susie pass through, they find themselves in the Light World outside Kris's house, having exited the Dark World even though smoke pouring from the Dreemurs' front door indicates that TV World's Dark Fountain is still open inside.
Chapter 4[]
The Great Door in the Closet Dark World is still closed as before. The Bloxxer's head is found on the floor with its legs and five pairs of pants stacked beside it, explaining that their legs have gained an ultra-instinct which allows them to lead an independent life. The Little Ball may also be present.
The Roaring Knight uses a Great Door to flee from a Dark World in the church lobby's Dark Sanctuary to a second Dark World inside the building's Main Hall, slamming the door behind them so the party is forced to find another way through.