So do all of the PR series all take place in the same universe? I've never watched it since the first series back when I was a kid, and I had assumed each time the title changed it was a totally different story and universe.
There is some disagreement about whether RPM took place in the same universe as the other shows, but otherwise all the rest of the seasons undeniably take place in the same universe. (Though Mighty Morphin Power Rangers: The Movie does not, for a number of reasons).
In the RPM/Samurai teamup episode of the previous incarnation of PR (Samurai), the Red RPM ranger came from "another dimension". This would seem to confirm the already existing belief some had that RPM was in its own separate continuity, though some still think that RPM does take place in the same universe as the rest, and that the Red RPM ranger we saw in that teamup episode was an alternate version from a different universe (The fact that RPM Red was acting out of character certainly supports the latter).
And to add more fuel to the fire, RPM rangers can be seen in behind the scenes shots of the filming of next year's Legend War battle.
As for me personally, I had
believed that RPM was in an alternate universe, but the RPM rangers being present in the mega teamup next year is giving me doubts.