Quote Originally Posted by Tavrobel
Buy FFX before playing FFX-2. But either way, you will be severly disappointed by FFX-2, whether you expect to play through another FFX, or whether you play it alone. It rates fine if you compared it every other game made in history. But for a FF, it lacks, plotwise and symbolicly. Horribly.
This is the truth.

Challenging? FFX-2? Did you seriously use that word?
Yes, I did.
FFX-2 follows the systems in FFVII and VIII with a three man party, and is faster, but not at all challenging.
It's not the same battle system. Did Yuna use materia? No. Not the same.
It is faster and different from what has been seen in previous games. Which can be challenging for someone who is used to playing by the old battle systems. Once you get used to it it's alright.