can i answer with "all anime" ? :3

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I don't really watch a lot of anime. I watched a few episodes of SAO with my girlfriend, and it had me groaning pretty much the whole time. Other than that, Bokurano comes to mind for "most disappointing." The manga is excellent, but the director of the anime openly admitted that he hated it and made as many changes as he could, radically altering the tone and story. I didn't finish it, but it feels like a shadow of the manga.

Hard to say worst [I, y'know, try and NOT remember those :P].

Most disappointing was definitely Sailor Moon Crystal, though.
Rushed storylines, weak characters missing all of the charm of the original TV series, etc.
Just wasn't any fun at all :(

I've only watch Avatar and liked it ..

There's many titles that i can call 'really bad' and i can't decide which was the worst.
Yozakura Quartet (2008) maybe?

I didn't watched a lot of them, but i obviously don't like Fullmetal Alchemist

It's a toss up between .hack//Roots and Jyuushin Enbu.
For .hack, I'd been enjoying the series for the most part up until Roots, which was like hitting a brick wall. Could barely keep myself awake through the first few episodes
Jyuushin Enbu was a massive disapointment, mostly because, having been created by the same person behind Fullmetal Alchemist, I had high expectations... Wouldn't even consider this one to be of average-quality.

Kimi no Iru Machi for sure

is there such a thing: bad anime?

if i had to choose i would maybe say the newer Pokemonstuff, even if that doesn`t count.

I don't watch anime

D.Gray-man
I watched the entire show HYPED becouse is SO GOOD (opnion) then, its simply over. Without much explanations.

A year later, i discover that the author got sick, stoped the manga AND the anime. So i gave him a discount. Dunno whats happened ever since. I will have to google it later. And if he gave us a continuation, i will have to watch the original again. e.e'

I"m not a big fan of anime but I remember that I did not enjoy "Halo Legend"

BLOOD C.
It's simply downgraded from the previous BLOOD+. Just killing or being killed by monsters like cheap horror movie.
BLOOD+ was one of the bests for me though.

Hellsing Ultimate. Everyone makes a big deal about how much better it is than the 2001 version... Well, in this remake, the art style is inconsistent with the Manga (and comparatively ugly), and the story left out so much context that it made no sense.

Also, Dragonball GT was bad.

easy and simple
BF4 ... cuz bf4.exe stop responding

I watch only ones with good reviews, so I can't answer this question. Wasn't disappointed by anime even once :3

Chobits, I remember liking the manga when I was young, but recently when I tried to watch the anime.. Well, I hated it to say the least.

I don't watch a lot, so my selection is limited, but Kotoura-san was quite disappointing; started interesting but then just sort of... meh'ed out.

Anime ok? Not manga.. Not LN!
Sword art online
And
Dungeon ni Deai wo Motomeru no wa Machigatteiru Darou ka
*run away faster than light speed

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