I have this game for the DS. Get it, imported, because thats the only way you will get to play it.
Just a few playable, characters, i could remember
Goku
Vegeta
Piccolo
Gohan
Yusuke
Kenshin
Naruto
Sasuke
Sakura
Yugi
Shaman king guy
Bleach guy(ichigo0
Dr slump girl
akira tor man from slump
Luffy
hunter x hunter main guy
other one piece people
and like 50 others!!!!
Dragon Ball
Son Goku
Super Saiyan Goku
Super Saiyan Son Gohan [adult]
Super Saiyan Son Gohan [boy]
Son Gohan [boy]
Super Saiyan Vegeta
Vegeta Piccolo
Kuririn
Chi Chi [& Son Goku]
Kamesenin
Bulma
Dende
KamiSama
Potara Earrings [item]
Senzu Bean [item]
Eyeshield 21
Sena Kobayakawa
Hiruma Youichi
Kurita Ryoukan
Tarou Raimon
Cerberos
Mamori Hunter x Hunter
Gon Freaks
Killua Zoldick
Kurapica
Ichigo 100%
Aya Toujou
Tsukasa Nishino
Satsuki Kitaooji
Yui Minamito Hikaru no Go
Hikaru Shindou / Fujiwara-no-Sai
Katekyo Hitman Reborn!
Tsunayoshi Sawada / Reborn
Rambo Pyuu to Fuku! Jaguar
Jaguar Jun-Ichi
Piyo Gen
Hammer
Gintama
Gintoki Sakata
Shinpachi Shimura
Kagura Busou Renkin
Kazuki Mutou
Tokiko Tsumura
Captain Bravo
Kochikame
Ryotsu Kankichi
Keiichi Nakagawa
Reiko Akimoto
Daijiro Ohara
Maria Black Cat
Train Heartnet
Sven Vollfied
Eve
Shaman King
Yoh Asakura
Anna Kyoyama
Hao Asakura & SOF
(Spirit of Fire)
Horo Horo
Manta Oyamada Bobobo-bo Bo-bobo
Bobobo-bo Bo-bobo
Don Patch
Tokoro Angel
Heppokomaru
Dengaku Man
Girlfriend
Beauty
Hatenkou
The Service Man
D.Gray-man
Allen Walker
Rabi Mr. Fullswing
Saruno Amakuni
Death Note
Light Yagami / Ryuuk
L Yu-Gi-Oh!
Yugi Moto
Prince of Tennis
(Tennis No Ouji-Sama)
Ryoma Echizen
Kunimitsu Tezuka
Shusuke Fuji
Takeshi Momoshiro
Kaoru Kaidoh
Eiji Kikumaru & Shuichiro Oishi
Sadaharu Inui YuYu Hakusho
Yusuke Urameshi
Kurama
Hiei
Kazuma Kuwabara
Rurouni Kenshin
Kenshin Himura
Hajime Saito
Sanosuke Sagara Naruto
Naruto Uzumaki
Sasuke Uchiha
Sakura Haruno
Hatake Kakashi
Hinata Hyuuga
Neji Hyuuga
Rock Lee
Shikamaru Nara
Tsunade
One Piece
Monkey D. Luffy
Roronoa Zoro
Nami
Sanji
Nico Robin
Usopp
Tony Tony Chopper Bleach
Ichigo Kurosaki
Rukia Kuchiki
Only like the main characters of the show, and the rest are helpers. So ask and I will tell you. I am not sure who else in shaman king besides that girl with the red thing and Yoh.