Is it staying true and loyal to the plot, characters, and not diverging from the storylines in the manga? (fillers don't count)
Then the BEST are: Naruto, Bleach, Death Note, Hunter X Hunter, Full Metal Alchemist
Is it taking a mediocre manga and making it better? Or taking a great manga and bringing it to life. (these are all titles where i watched the anime before reading the manga. i'm not sure if i would have enjoyed reading the manga as much if i did not have the images of the animated characters in my head before hand.)
Then the BEST are: Samurai Champloo, Hajime No Ippo, Rurouni Kenshin (up to the Kyoto Arc), Hikaru No Go, Full Metal Panic
I try to avoid bad anime titles, but if forced to choose I would have to say the Violinist of Hameln anime adaptation was probably one of the WORST I have seen. GREAT manga, but the anime did not capture any of the same feeling. The OVA did, but that was only one movie.
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