 If you liked
Gantz
|
 ...then you might like
Eden: It's an Endless World!
|
both contain extreme violence and people just trying to survive in the situations they find themselves
Sci-fi, lots of violence and cruel deaths, nudity, sex, despair, shock value. If you're in the mood for reading a manga that has those elements in spades, give GANTZ or Eden a try.
Element of surprise and violence are adapted into both series. Gantz and Eden: It's an Endless World crafts as story with sci-fi themes. The concept of survival also becomes pivotal as characters are put into dangerous situations. Also, be wary of violence in both series as it aims towards a more mature audience. Nonetheless, both be considered for their suspense and characters who plays dynamic roles in these two series.