X-Files, sword and sorcery styles!

[thingswithwings]

Hey, everyone. I'm looking for a very old story. In it, Mulder and Scully get pulled into an alternate universe where they become (respectively) a magician and a warrior/healer. They ride horses and fight with swords and things! Then after years they finally make it back to their universe, where only a couple days or something has passed. It was quite a long story, possibly with many sequels. C'mon, you remember that one, don't you? Help a girl out.

Thanks in advance!