Do you know any manga similar to dorohedoro . I really liked the dark mysterious plot with action and all these features ! Devil exam, death wandering around town, two different worlds zombies an so on.
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closest thing i can think of is blood lad but its kinda more shounen and dorohedoro is more seinen

I wish..
Appleseed is most similar maybe.

Other series with some of the same vibe:
Akira
Blood Lad
Maken X
Blame!
BioMega
Hunter X Hunter

Yes it will be very difficult to find something similar or remotely unique as Dorohedoro but I will give you some that are kind of like it. Dont expect it to be as good cause they wont be.

Zetman very dark plot, with badass main with realistic drawing.
Akumetsu will enjoy if your interested in government corruption
Eden: It's an Endless World! the closest thing I can think of that matches dorohedoro's craziness

I got way more but I think these three will keep you busy for a while. Also these are all must reads in my opinion if you like a good mature dark manga

Freesia
Alive although its a shonen, its fairly hardcore for one
Dogs: Bullets & Carnage
Tokyo Akazukin

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