Portal (Gameplay element)
Portals are a gameplay element introduced in Kingdom Hearts 3D: Dream Drop Distance. They are a special type of communication system that allow characters from various Dream Worlds communicate, sometimes, even transport from one version of that world to another. These Portals usually manifest physically as orbs with various spikes around them, with the image of that world inside the orb.
Kingdom Hearts 3D: Dream Drop Distance
When Riku arrives in Traverse Town, he meets Joshua, who asks Riku if he came through a Portal. Joshua explains that the world is split in half and that one can use a Portal to pass between the different versions of Traverse Town, and he asks Riku to find Rhyme, who is the key to the Portal.
Sora and Rhyme encounter Neku on a rooftop in the Fifth District, and Sora asks him if Rhyme is his game partner. Rhyme suddenly disappears, and the mysterious youth appears and summons the Hockomonkey. After defeating it, Sora and his friends are temporarily able to see events occurring in the other Traverse Town, and a Portal materializes, through which Joshua and Rhyme appear. Joshua explains that Traverse Town is split in two, and that Rhyme's dreams are his Portal, which allow him to travel between the two towns.
Kingdom Hearts III
At the Keyblade Graveyard after Master Xehanort successfully obtained the χ-blade and Kingdom Hearts, Riku suggests using a Portal to stop him. While the rest of the guardians of light hold Kingdom Hearts back, Sora, Donald, and Goofy use Sora's Keyblade to open a Portal from within Xehanort, sending all four of them to Scala ad Caelum.
Kingdom Hearts Melody of Memory
On the search for Sora after he disappeared from misusing the power of waking, the Fairy Godmother takes Riku and Kairi to The Final World, where they meet the Nameless Star. The Nameless Star opens a Portal to the world of Quadratum and Riku uses the power of waking to travel to it.
Link Portals are a type of portal that can be found in all Sleeping Worlds. They give special challenges for the protagonists, Rare Nightmares to battle, other Spirit's party or even allow them to battle stronger versions of the bosses, rewarding the player with Droplets, Dream Pieces, and other prizes if they are completed. Each portal belongs to a "player", usually named from a Final Fantasy character, like Auron, for example.
After the first few drops, Link Portals begin appearing throughout the worlds. They are displayed as pink dots in the lower Touch Screen, but they can't be seen in the top screen. When the player moves near the point where the portal is located, a small sign with the name of the owner, the difficulty rank, represented by five stars, and a symbol of the type of challenge or the Spirit Party of the portal will appear in the Touch Screen. If the player touches that sign, more details about the Link Portal will appear in the top screen. After reading the details, the player can decide to open or not the Link Portal.
There are four different types of Link Portals: