Rather than show a few scans and say what was good or bad about the book, I'm going to recount all of the good fight scenes because honestly, these three books are nothing BUT big running fight scenes and there's not much plot to discuss.
FIGHT ONE: Soranik and Iolande Vs. A Morgue Full Of Black Lanterns
WINNER: TKO To The Green Lanterns, who manage to hold the zombies off AND evacuate all of the still living patients from the hospital on Oa.
FIGHT TWO: Guy Gardner Vs. Black Lantern Ke'Haan
WINNER: Guy Gardner, who burns the meat right off of his former fallen comrade... only to see the ring fly off and look for a new host.
FIGHT THREE: Soranik VS. Zombie Jade
WINNER: Uncertain, but Soranik gets in a wicked punch in the last panel she appears in.
FIGHT FOUR: Arisia VS. Every Member of Her Family Who Was A Green Lantern
WINNER: Arisia, who burns through all three of them at once.
FIGHT FIVE: Kilowog VS. His Former Drill Sargent, Lantern Ermey.
WINNER: Kilowog, who beats seven kinds of crap out of the zombified corpse of his former teacher and is quite happy to do so.
FIGHT SIX: Green Lanterns Vath and Isamot VS. A LOT of Black Lanterns, including the Zombie Children Of The White Loeb.
WINNER: The Lanterns, as an Indigo Lantern shows up and mixes his light with theirs to disable the Black Lanterns.
You want high-action, zombie-slaying in space? This book has it in spades! Well worth reading, even if it weren't a major tie-in to the series.