If you liked
One Piece
|
...then you might like
Lupin III: Episode 0 "First Contact"
|
Similar expressive character design, animation and type of humour. Great characters and stories in both, but they're not much alike in these items. Goemon reminds me of Zoro and Fujiko resembles me of Nami, though.
If you liked
Fate/Zero
|
...then you might like
Persona 4 the Animation
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People summoning creatures to fight in their commands. The art style is similar too. Although Persona have a lot of comedy, while Fate/Zero is darkly serious.
If you liked
Mahou Shoujo Lyrical Nanoha A's
|
...then you might like
Night Wizard
|
Teenagers battling using magical weapons, with some overpowered techniques. Also, similar endings. Nanoha A's have much better story and characters, though.
If you liked
Turn A Gundam
|
...then you might like
Ginga Eiyuu Densetsu
|
Both are epic old school sci-fi series with clever plotwists, great battles and political plots.
If you liked
Tentai Senshi Sunred
|
...then you might like
Arakawa Under the Bridge
|
Totally insane comedies. Arakawa's animation resembles Sunred's too, in my opinion.
If you liked
Rockman.EXE
|
...then you might like
Heroman
|
Same American feeling (stronger on Heroman, but still). They're about a boy with a technological partner who fights against computer viruses (on Rockman.EXE) or aliens (Heroman). Both are intended for young audience.
If you liked
Maigo
|
...then you might like
Bokura ni Matsuwaru etc.
|
Both are collections of shounen ai/yaoi oneshots. Both are really great.
If you liked
JoJo no Kimyou na Bouken
|
...then you might like
Blue Dragon
|
Shadows and Stands are very similar. But everything else are pretty different. Jojo's have a lot of blood and tense feelings, Blue Dragon is more childish and funny.
If you liked
Luno
|
...then you might like
Hatsukanezumi no Jikan
|
Both mangas created by Toume Kei. Same style, same feelling, but Luno have fantasy and magic.
If you liked
Slam Dunk
|
...then you might like
Real
|
Great mangas of Takehiko Inoue. Both are about basketball, with a familiar mood. Slam Dunk have more comedy and REAL have more drama. Both are awesome. If you don't like basketball or do not enjoy sports manga, read Slam Dunk first. I'm sure you'll love it and you'll want to play basketball.
If you liked
One Piece
|
...then you might like
Jibaku-kun
|
They have the same strong adventure shonen feeling.
If you liked
Shaman King
|
...then you might like
Jibaku-kun
|
Both are adventure shonen and feature a group of heroes trying to achieve their objective through magic battles.