Via io9.com:

This Saturday on Star Wars Rebels, Darth Maul finally faces down with Obi-Wan Kenobi. It’s the rematch he’s been waiting for since The Phantom Menace, when Kenobi cut him in two and derailed his rise to power. But it was a battle that was never supposed to happen.

Leading into Saturday’s must-see episode “Twin Suns” (we’ve seen it, it’s incredible), io9 spoke with Rebels executive producer Dave Filoni about the pressure and importance of finally bringing this Star Wars battle to life. We won’t mention any spoilers here, but Filoni did reveal this: “Originally Maul perished in the season two finale where he returned. It was a one-off appearance.”

In case you don’t remember, after his first battle with Obi-Wan Kenobi in 1999’s The Phantom Menace, Darth Maul came back on Filoni’s first show, The Clone Wars, sporting some brand new robot legs and some family connections. He had a huge storyarc there, and later reemerged on Rebels as a mysterious figure who used Ezra Bridger’s emerging knowledge of the Force to his own benefit. Filoni’s original idea was to bring him back and give fans something they’d always wanted, to see the popular Sith Lords battle it out.

“So originally in that episode you were gonna get Vader fighting Maul, Vader would have killed Maul, and then fought Ahsoka,” Filoni said. However, in the already jam-packed episode, he decided it was just too much.

“It just became unwieldy,” Filoni continued. “There were too many storylines, and there isn’t enough emotional material between Vader and Maul. It’s more of a fan fiction fun thought that they fought. The emotional drama was really between Vader and Ahsoka. So we decided to let Maul live.”

But alive, Maul became a great tool for Filoni and company. He’s played a minor, but vital, role in the ongoing third season: First he and Ezra unlocked some crucial Star Wars information, he’s was the person who provided a link between Sabine and the Darksaber and, now, he’s going to finally have a showdown with Obi-Wan Kenobi.

Filoni wasn’t sure if that was how he wanted the story to go but, ultimately, it benefited both characters. “You always felt Obi-Wan had this great track record of taking out a Sith Lord in the past,” Filoni said, referring to his first battle with Maul which is referenced throughout the prequels. “We wondered, [by bringing back Maul], did we rob him of what he was able to accomplish?”

Everyone in the world will find out Saturday at 8:30 pm ET on Disney XD. And check back here immediately after the episode airs for an exclusive interview with Filoni on the finale’s (many) revelations and surprises.