The "Planet of the Vampires" issue! Campy fun, no doubt a Kirby "Transylvane" homage. Also, I kept thinking Countess Bezelbeth was Mandrak's daughter but I guess it's Starbreaker the Controller (???)
The covers have that super detailed airbrushed look and some splashes (and even individual panels on pages) seem to have the same look in b&w. The art is by a guy named Denis Beauvais who was mostly a paperback cover painter from what I can find.
for those at home, this is basically the same ending as Morrison's WW3 storyline in JLA. The big difference is, giving everyone superpowers is the solution to a cosmic threat, not some kind of dangerous "anarchy"