Dimensional rift

The dimensional rift is the space in between the A.R. Worlds, which are traversable via the dimensional wall. The dimensional rift itself appears an otherwise empty space filled with a purple mist, a scene one might confuse for.

In Super Hero Taisen, the vast majority of Kamen Riders and Super Sentai are respectively sent to the dimensional rift, under the pretense of being defeated, by and Kamen Rider Decade. Indeed, upon "killing" their enemies, Marvelous and Tsukasa's respective weapons appeared to emit the same purple mist found in the dimensional rift, which is seen to envelope their targets before vanishing them.

Ultimately, all the Kamen Riders and Super Sentai, whom had been presumed to be wiped out, returned from the rift via the dimensional walls as Tsukasa and Marvelous revealed their ruse to defeat the Shocker-Zangyack Alliance.