I imagine in order to save Isa, Lea's going to end up having to fight and pwn him. It's a man thing.
Personally, though, I would prefer for Isa to remain a tragic villain (or maybe a Snape-esque hero). The series really needs to acknowledge that everyone can not be saved; I think Isa is the perfect character with which to explore that element. But that's not what this thread is about.
The thing is that up to now we do not even really
know if Isa
qualifies as a tragic villain. People are quick in deducing that he's more in a victim-role like Terra when it is still entirely possible that he's willngly on the whole boat just like Braig.
Not to mention Nomura tends to mention Isa in tandem with
Braig, not with Terra when he speaks about circumstances.
And why does the series
need to acknowledge that? What if Nomura doesn't
want to acknowledge something like that because it has no room in the fantasy universe like the one he has imagined?
Even IF something like this would happen, it could very well serve as a plot point in the next saga to save those who couldn't be saved in the final showdown against Xehanort, as for example Lea getting a "spin-off" game of his own in the next saga (possibly with Roxas and Xion as party members) to search for a way to bring back Isa, stumbling upon some machinations of the new villain(s) in the process which would only make sense once you play the next (main) title with Sora.
It's not something I would put past the writers to pull off.
Also, somewhat off topic: this is going to be the first main KH game, where Sora isn't looking for Riku and/or Kairi. Hallelujah and praise the Lord. Not that I disliked that in any regard (I love it, actually!), but it's nice it's about saving TVA and RXN (and possibly even AtW and ME) this time. It keeps the same awesome KH formula, but changes it up just enough, so it doesn't feel like a complete rehash. And it's nice that hopefully SRK might get to see each other more in this game, when usually they're separated. Yeah...
That's actually something I thought about too. Besides the "save a bunch of people"-thingy, this time around they also have a firm second goal that goes beyond just "beat up Heartless to protect the worlds" as Xehanort and his machinations to unleash a new all-destructive war over the universe is a threat way bigger than the puny mook-armies of the Heartless.
I certainly hope so as well, not only for SRK but for the whole main cast. It would be nice to see Kairi interact more with Donald and Goofy, Riku, Aqua, Mickey and all the others, same goes for Sora, Riku and the other main original characters.
While the initial setup looks just again like it's a total separation with Mickey and Riku going off on their own and not a single mention of Kairi while Sora again gets to roam the Disney worlds only with Donald and Goofy on a wild goose chase after an ominous key (Nomura has already confirmed that part), it remains to hope that they will a) really
search for that damn key and take the godamn thing seriously instead of just forgetting about it once they are five minutes into a Disney world and go then on happy rehashing of the movie plot and b) it won't last for 90% of the game.
Let them only half of the game do with the old formula and then move on to something new, let them reunite with Mickey and Riku and actually allow them into your party, possibly Lea and Kairi as well.
Don't make the same errors as in KH 2 that you only always see SDG's antics in the Disney worlds and have all other characters do their (important to the overall plot) stuff behind the scenes and learn nothing about them until a short cutscene in the second-to-last world or something.