i think the only jrpgs that have had good difficulty (that i've played) have been wild arms 5, shadow hearts 3, and, more recently, FFXIII-2
not that they were particularly challenging, but most JRPGs are just too easy (FFX, SH2, XS3), a complete chore (SH1, XS2, FFXIII), or both (FF8, FF9). WA5, SH3, and XIII-2 manage some kind of balance between being too simple and being too tedious that really make them fun to play despite having pretty weak plots. I guess I should give nods to DQ8 and XS1, both of which could have afforded faster battles despite being a lot of fun.
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XS2 is the only good Xenosaga game - Lady Ashe
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