Avengers Initiative #18 Zombie Variant (2008) Secret Invasion Marvel comic book. Written by DAN SLOTT & CHRISTOS N. GAGE, Penciled by STEFANO CASELLI, Cover by MARK BROOKS. SECRET INVASION TIE-IN! THE EXPLOSIVE FINALE STARTS HERE! Now that the KILL KREW knows Skrullowjacket's master plan, can they stop the TRUE purpose of the Fifty State Initiative? Plus:It's THOR GIRL vs. ULTRA GIRL!One is more than she appears to be... and the other's a Skrull. And, after fourteen issues, are we REALLY going to unmask MUTANT ZERO?!