The final area of Exile II US is what separates the hardcore gamers from the up and coming gamers. I'll break down its defeat by area.
Tower Of Souls
Best Character: Rumi
The biggest problem here are the giant bats. They'll chase you if you get too close. The easiest way to beat them is to scroll just far enough where they're circling about halfway into the screen, then toss knives at them. If they take damage and that damage doesn't recover (if they go too far offscreen, their damage recovers, remember that), then you can beat them easily. If you get too close, they'll chase you, and the only way to shake them is to just keep walking away; they'll eventually just start circling again. If you have to leave the screen, remember that you have to fight them all over again.
The pink bitches are the easiest enemies. You can peg them from afar easily, or simply hop over them and shoot if they get too close. Alternately, you can shoot downwards from above them. Way too easy to beat.
The dragons cannot be defeated with weapons. Fortunately (with only one exception, which is near the top of the tower), they only appear when all the other enemies in the area are already out of your way. What you do is allow them to to follow you (don't go too far away or they'll simply go back to where they were; keep them in view at all times!) and then jump up onto the platform, evading their jumps. Make sure they follow you to the exit or you'll get a painful surprise when you get there.
The Great Ark
Best Character: Rumi or Sadler
The most annoying enemy here is the white guy with a stick, as he can shoot a ground wave at you for major damage. It's best to use Rumi for most of this part, since she can hit him from a distance. You really have to go slowly through this area until you know it well enough to know when these bastards are gonna show up. If you keep a good distance from them, they won't attack, and you can slaughter them at your leisure.
There's a blue variant of the previous enemy that does nothing except swing at you when you get too close. Very easy to take out.
Then there's the little magician guy, he can be annoying. If you get too close, he'll charge up his staff and shoot out a lightning bolt. Sadler is best for taking this punk out, since his attacks are strong and fast, plus agile enough to move out of the way before the lightning comes out.
The big problem with The Great Ark is the sub-boss, Djinn. He's the strongest boss in the game. I recommend Sadler for him, or Rumi if you're not feeling confident in getting too close. Djinn has four attacks: a wind projectile, a lightning bolt, a ground wave, and a body rush. Fortunately, Djinn settles into a pattern after a few moves. How to know his moves:
Ground wave: he puts both of his arms to his face, then throws them outward. Easy to jump over, you can land right next to him and score at least three hits.
Wind projectile: he puts his hand in the air and starts spinning the projectile on his finger. This can be jumped over, getting in one or two attacks.
Lightning bolt: He puts out his hand and shoots lightning about half a screen wide. Don't bother trying to counterattack; if you don't get hit, you won't make it in time to attack anyways.
Body rush: When he lands, he does nothing except sit there for a moment...and then he charges across the screen. A well-timed jump over his attack will allow you time for at least two solid hits.
Hanging Garden
Best Character: Rumi or Sadler
Don't leave this area without finding Sadler's best equipment. If you can't find it, keep looking around until you do.
This area is rather easy compared to what you've already faced. The first menace is a threesome of elemental attackers than circle together. Rumi will be able to take out these punks with ease, as long as you watch out for the blue energy ball that the blue one occasionally shoots at you. Try to keep your distance; get close too any one of them and they have close-up attacks as well which really hurt.
There is only one other enemy here, which are these strange flying lion-type creatures. They won't attack you, and can be used as "stepping stones", so to speak. You can kill them for a decent amount of experience, but you'd better be level 16 by now anyways.
Central Garden
Best Character: Anyone
If you haven't gotten Sadler's best equipment yet, go back into the Hanging Garden and find it.
There are no enemies here, so anyone works.
Inner Sanctum
Best Character: Sadler
You can only use Sadler for this area. Win here and you win the game.