Coming two months after the end of "The Thanos Imperative" and two months before the beginning of "The Annihilators," "Devastation" acts as a bridge for the two series, one that's necessary and extremely tedious. Think of it as a calling to arms issue as Cosmo, the former Guardian of the Galaxy, carries out Star-Lord's final wish by gathering a new Guardians-type of group. Sorry, I accidentally just spoiled the entire comic for you. That's how unessential and tedious it is: it is the premise and it's about as exciting as you'd expect from it. It's a comic where the story is the premise and fans will be excited because the characters they love are in a comic book, doesn't matter what little happens.
The issue begins with an interesting and immediately compelling premise of Blastaar attacking the Inhumans/Kree in the wake of the invasion from the Cancerverse, taking advantage of their weakness. Never mind that he was an ally in that conflict. From there, the fight against Blastaar's forces is interspersed with Cosmo recruiting heroes to the Annihilators while being suitably vague about it at the same time so readers don't jump the gun too much.
This isn't an unusual sort of comic and, once, would have been the first six pages of a comic with an actual plot. There's no mystery in where things are going and not much gained on the journey besides the occasional scene that shows a little more flair for character work than the rest. By the time the group is assembled, there's just enough space for a quick cliffhanger and a promise that the sort will continue (or, begin) in two months. It's an exercise in hand-holding storytelling and something that Abnett and Lanning have largely avoided to this point.
Not helping is the art of Miguel Sepulveda, or, rather, the art of Miguel Sepulveda and Rain Beredo. Sepulveda showed a strong photoreference streak in his work on "The Thanos Imperative" with panels often showing characters clearly divorced from the backgrounds and one another. That effect is even more pronounced with Beredo's heavy-handed colors that create an effect where characters don't look like they belong in the same comic. And that's fine if you want to present a 'realistic' portrait of how aliens may look standing next to one another, but not if you want anything resembling coherent, attractive art.
If you're planning on picking up "The Annihilators" in March, "Devastation" seems utterly inessential unless you absolutely have to see Cosmo gather the team. It's not worth an entire issue and comes off as filler between the end of "The Thanos Imperative" and the beginning of "The Annihilators." It's excessive and indulgent and simply not worth it.