So, it's obvious there will be a battle with a corrupted Baymax, which begs the question, which has probably already been discussed (sorry if it has) is the portal where Baymax was lost "The Lanes Between Worlds" it certainly looks similar when Hiro goes into it.

The Lanes Between Worlds can only be accessed via Keyblade if I recall correctly. And in the movie it was just 'another dimension'.

The Lanes Between Worlds can only be accessed via Keyblade if I recall correctly. And in the movie it was just 'another dimension'.

 

I'm pretty certain that you're correct on that, but: 

 

(Courtesy of kingdomhearts wikia)

 

There are five known ways to travel through the worlds:

• The "Star Shard" that Mickey took from Yen Sid to travel across worlds during Kingdom Hearts Birth by Sleep. The downside to this method of travel is that if the user does not know how to control the shard, the destination and time of activation will be random.
• Utilizing the Corridors of Darkness; this is a faster means of travel than the Gummi Ships, but those who use them are at great risk of being corrupted or destroyed by the darkness.
• Teleportation, used by beings that possess powerful magic; Merlin was able to teleport himself, Sora, Donald, and Goofy from Hollow Bastion/Radiant Garden to Disney Castle, as well as teleport Scrooge McDuck to Radiant Garden in Birth By Sleep. Maleficent is also capable of teleportation between worlds.
• Keyblade Glider; Terra, Aqua, and Ventus can change into their armored form and turn their Keyblades into vehicles that can travel to other worlds by using the Lanes Between.
• Time travel, such as used by Ansem, Seeker of Darkness, Young Xehanort, Yen Sid and Pete. However, Young Xehanort's method of time travel is trickier than the Yen Sid and Pete's; there needs to be a version of himself where he needs to go and he can only go backwards or forwards in time

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Edited January 6, 20169 yr by Recusant Sora

Actually, it is not the Lanes Between. It was just another dimension. Darkness unfortunately (in your case, fortunately) took the previous Baymax over. It probably won't do that in the Lanes Between.

No, the dimension in the film is not The Lanes Between, so my guess is that Xehanort somehow gets the means to nab Baymax from his dimensional prison, and then he corrupts him with darkness, causing him to turn into Dark Baymax!  I'm very intrigued by how this will work out when we witness the story firsthand!