Sephiroth?! D:

1. Decisive Pumpkin keyblade works best! But if you have the ultima, that works too!
2. Equip alot of elixers cause you will need them
3. You need guard, aerial recovery, high jump, aerial dodge, aerial finish, slide dash, aerial sweep, aerial spiral, scan but all the combo stuff is optional but it does help
4. You need custom buttons too, maybe set reflect and elixer as your custom buttons.

Tips:
1. for his slashing attacks, ALWAYS guard those, then after, attack him
the easiest way to make his first form easy, just guard his slashing attacks, and then use counter guard. (dont move too far away or his attack pattern will change)
2. Sephiroth will teleport and knock you up the air, when this happens, if you hear him teleport again, use aerial recovery then find him and attack. To avoid this though, guard as soon as he teleports.
3. for his second form, he surrounds you with black orbs. Quickly reflega to get rid of them, if you reflect too much, he will cast more. (of course he does his slashing so guard them) If you get too close while failing to stun him, he will do his fire pillar attack.
4. When he says "perish" run away from him, VERY far away.
5. When you hear him start to say "Decend Heartless Angel", lock on him immediatly and high jump+aerial dodge to him and attack him (be very fast!) hit him at least once to stop his attack, if you didn't hit him after he finishes saying "angel" basically almost ALL of your HP is GONE except one, so quicky put a elixer on yourself to heal.
6. In sephiroth's final form, he will do a meteor attack, simply run, right to left using high jump+aerial dodge. You shouldn't get hit at all.

You might lose 3 or 4 times but when you get used to this, you will win shortly!


All thats left of the battle is all his slashing stuff, so just guard then attack and you automatically win. Basically, you don't need to use drive, limit, summon or anything for this battle.

 

There are many people who asked how to beat sephiroth. Here's the battle guide video:
YouTube - Kingdom Hearts II - Sephiroth Battle Guide

I beat him level 52 with kingdom key in proud mode.

 

try this site

How to Beat Sephiroth in Kingdom Hearts 2 - wikiHow