I'm a huge Kingdom Hearts fan. I didn't play the first game when it came out, I played it a couple years later. And I didn't beat it until after I had already gotten and played Kingdom Hearts II. I love both games greatly, I can't choose which one of the two is better.
But Birth by Sleep for the PSP is the best Kingdom Hearts game. I don't say that lightly, because every other spin-off they've had were decent at best. It seemed like they really put their best effort into BBS though, it's got so much of that amazing charm, warmth, and emotion that you experience in the first and second game. It's truly worthy of the Kingdom Hearts title, and I highly insist, almost beg, that you play it.
It's a prequel, set 10 years earlier than the first game, and it offers a whole lot to the overall story of KH. The characters are actually better than Sora and his friends.
If you don't have a PSP, then you should get one. If you don't want to get a PSP for just one game (one of the best games ever though) then I think they plan on making an HD version of it later on for the PS3. So you can get it and play it then. I hope they do that, because I'm perfectly willing to pay money for it all over again to see it in HD on my awesome TV.
ALSO, one more thing, the ending of BBS sets up for Kingdom Hearts 3.
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~Halo Now you learn the mistake of challenging me.
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