After a few issues of fairly entertaining stories about the new "X-Force", Yost and Kyle really grabbed the attention of all X-Fans on the final pages issue four when Angel was once again transformed into Archangel by the Purifiers. It's a little upsetting, if not entirely unexpected, that this issue doesn't really give us any new information on the transformation beyond "it has happened," and the all-important question of how permanent this change might be goes utterly unaddressed as the story charges on.
Archangel's re-appearance does give the title a new, dramatic thrust and helps bring the first arc towards some kind of climax. The pacing of the series has been a little strange -- a lot of important-seeming things suddenly happen in this issue without the corresponding build-up, and the amount of time afforded certain characters in the Purifiers' ranks gives them undue prominence despite their one-dimensionality. Even Bastion, the most interesting addition to the Purifiers, gets sidelined as a result.
Kyle and Yost are clearly attempting to tie in many elements of existing continuity, and the frequent references are both pleasing for older readers and sufficiently placed so as not to alienate newer ones, generally speaking. If there's any one problem with the title's approach to its position in the X-Men line of books, it's that X-Force's mandate hasn't really been solidified. It's now clear that Rahne's biological father and his appearance in the Purifiers ties her into the team, and Archangel may yet prove to be a new member, but already we find the crew on their back heels, just like any other X-Men team would be in similar circumstances; their most effective appearances require them to be taking the offensive.
Speaking of the offensive, it's actually quite astonishing to see what Marvel are allowing Kyle, Yost and Crain to get away with in the pages of "X-Force". There's a lot of graphic brutality in the title and the bleakness is nothing short of unrelenting, with Rahne still experiencing the negative effects of the drugs she was given and Archangel in a blind, despairing rage over the loss of his wings again. There's nothing close to a ray of sunshine in this story so far. Yost and Kyle are more at home with the tone than they were in "New X-Men", but it's arguable how much despair readers can take. No-one's asking for broad comedy and slapstick, but as they say, a change is as good as a rest -- anything a little less on the gloomy side, even for a second, would be a welcome addition to the title.