This is a review for Go Go Power Rangers Volumes 4 and 5, since they're basically one long story split into two, the same way as volumes 1 and 2 of the series were. I'm also assuming Volume 5 includes the Forever Rangers one-shot that ties up the story.
The focus on the early days of the Power Rangers continues here, as the team continue to feel out exactly what roles they play, as well as their relationships with each other, which blossom in some surprising ways.
Meanwhile, writer Ryan Parrott gives both the Green Power Coin and Rita Repulsa a hell of a lot more of a background, that sheds some light on why Rita is the way she is, and how she ends up further on in the series as well. It also manages to thread in and out of some continuity that the main Mighty Morphin' book set up, which was a nice surprise.
There's also a new wrinkle in the form of Alpha-1, the predecessor to Alpha-5 (no duh) who isn't exactly everything he says he is, and puts Zordon's methodology under a microscope in a surprising way.
On the art front, Dan Mora departs the series in favour of Eleonora Carlini, who I think has finally found her place in the comics world - she's bounced around at DC for a while but I never really felt like she suited the books she was assigned, but her work her is excellent. It's not as good as Mora's, but it's definitely damn close, and Raul Angulo's colours are gorgeous. The Zord battles have never looked so good.
As a bridging story between Shattered Grid and Necessary Evil, as well as an examination of the early days of both the Rangers and their villains, Go Go is doing a fantastic job, and these next two volumes are living proof.