The Reading order:
DC Nation #0 - Kicks everything off
EVENT: Justice League: No Justice
Justice League: No Justice #1-4
EVENT: Man of Steel
Man of Steel #1-6
Full arc review
Event: Flash War
The Flash Annual #1
The Flash #46-51
Full Arc Review
Event: The Wedding (Has some tie ins)
Batman: Preludes to the Wedding
Batman Prelude to the Wedding: Robin vs. Ra’s Al Ghul #1
Batman Prelude to the Wedding: Nightwing vs. Hush #1
Batman Prelude to the Wedding: Batgirl vs. The Riddler #1
Batman Prelude to the Wedding: Red Hood vs. Anarky #1
Batman Prelude to the Wedding: Harley Quinn vs. The Joker #1
Batman: The Wedding Part 2 (part 1 is in Phase 1 part 7)
Batman #48-50
#50 Review
Event: Aquaman/Suicide Squad: Sink Atlantis
Suicide Squad #45
Aquaman #39
Suicide Squad #46
Aquaman #40
And because I don’t know where to put it…
Suicide Squad Constriction Part 2 (part 1 is in Phase 1 part 7)
Suicide Squad Annual #1
Suicide Squad #47-50