Books like Justice League Unlimited
Adam Beechen, Paul D. Storrie, Carlos Barberi
Justice League Unlimited is 144 pages, about 2 hours 38 minutes at 250 words a minute.
12 books to read next
How long each takes
Renegades 10.7 h 
Spider-Man 5.3 h 
X-Men 3.3 h 
The Adventures of Captain Underpants 2.4 h 
The Amazing Spider-Man 2.6 h 
1602 4.6 h 
Pawn of Prophecy 5.0 h 
Avatar 1.7 h 
Buzz Boy and Fly Guy 31 min 
Sidekicks 4.1 h 
The Black Cauldron 4.1 h 
Ultimate Iron Man Volume 1 2.4 h Bar height shows length. Estimated at 250 words a minute.