I remember playing this game back in ~2006 - 2008 or so.
It was an online game where you had battle arenas and you collected different gems and such. There was 4 or so elements that you could use. The characters looked pretty animeish and you could upgrade your weapons (mostly swords I think). It was mostly a pvp game with some pve elements.
Gems were the currency to upgrade everything. --- MH3U - EliteNewbz