How did Ezra Bridger get to the World Between Worlds?

STAR WARS REBELS - "An Inside Man" - Seeking information on a new Imperial weapon, Ezra and Kanan infiltrate the Imperial factory on Lothal, but they must trust an unlikely ally to escape a lockdown of the building. This episode of “Star Wars Rebels” airs Saturday, December 3 (8:30-9:00 P.M. EST) on Disney XD. (Lucasfilm)EZRA, KANAN
STAR WARS REBELS - "An Inside Man" - Seeking information on a new Imperial weapon, Ezra and Kanan infiltrate the Imperial factory on Lothal, but they must trust an unlikely ally to escape a lockdown of the building. This episode of “Star Wars Rebels” airs Saturday, December 3 (8:30-9:00 P.M. EST) on Disney XD. (Lucasfilm)EZRA, KANAN

The final season of Star Wars Rebels introduced a unique concept of time travel into the Star Wars canon. In the episode titled “A World Between Worlds,” Ezra Bridger goes to the Jedi temple on Lothal, which is being guarded and excavated by the Empire because Emperor Palpatine wants to discover the temple’s secrets.

His access to the World Between Worlds begins in the episode titled “Wolves and a Door.” Ezra and Sabine find a mural on the outside of the temple of the Mortis gods that first appeared in The Clone Wars animated series and a pack of loth wolves. After some discussion with Sabine on the nature of the paintings, Ezra uses the Force to touch the painting, which changes it and causes the loth wolves in the painting to move away from the Mortis gods and form a round portal in the stone. Ezra rushes inside but isn’t sure at first what he’s encountering. This alternate dimension connects all time and space together. He hears several voices that Star Wars fans will recognize, including Rey and Kylo Ren, both of whom wouldn’t even be born for several more years, and Yoda, among others.

This World Between Worlds gives Ezra access to two recognizable moments from his past. He sees Ahsoka battling Darth Vader on Malachor, the last place Ezra saw Ahsoka alive, and in a moment of desperation, he pulls her out of the scene and into the World Between Worlds with him, saving Ahsoka’s life. He and Ahsoka then encounter a portal that shows the moments just before Kanan Jarrus’ death, and though Ezra wrestles with the possibility of saving his master from dying as well, he’s forced to make the impossible choice to allow the past to play out so that Kanan’s sacrifice for the good of everyone else still stands.

The World Between Worlds hasn’t been seen in Star Wars canon since, but its implications could have a serious impact on future Star Wars stories.