ps2 kingdon hearts 2. how to beat sipheroth?

Answer 1

Sephiroth is not as tough as you think he is. All
you really need to know is his attacks, times to heal
and when to attack. I beat Sephiroth at level 51!!You
can find Sephiroth Just beyond where Crystal Fissure and
the 1000 heartless battle was.

Things you must have is:

Curaga
Once More/ Second Chance
One Ether
The Rest of Items Hi Potions or all Elixers
Aerial Spiral (ability)
Combination Boost (ability)
High Jump lv. 1 at least
Finishing Leap (ability)
Explosion (ability)
Aerial Finish (ability)
Trinity Limit
Dodge Slash (ability)
Retaliating Slash (ability)
Upper Slash (ability)
Aerial Sweep (ability)
Counterguard (ability)
Fast mp regaining keychain

optional:
Glide ability
Auto Limit ability

you get most of those stuff from early bosses

Sephiroth's attacks (in order)
1.Moving Cut
2.Aerial Cut Combo
3.Cut Combo
4.Flash
5.Shadow Flare
6.Firaga Wall
7.Heartless Angel
8.Meteo

Alright here is how to defeat Sephiroth!:-)
Stage 1
At the very beginning be pressing triangle very fast
to dodge his very powerful MOVING CUT. Right after
that attack at him until he disapears. You have 2
choices now you can let him hit you into the air
and lock on and press square, triangle (counterguard)
and do aerial attacks. Or use the trinity limit. After
that get away and let him do his CUT COMBO. Immediatly
when he finishes his attack attack! He'll then attempt
to hit you in the air again.He also will start using
FLASH.

Stage 2
When 5 bars of health are down he will use SHADOW FLARE.
This creates balls that will start to go hit you. Avoid
this by hitting them. If he hasn't used CUT COMBO yet
attack him. He will try to get you off guard and use
Firaga Wall. Use your ether if you are far enough back.
Then use the Trinity Limit fast. Once done he uses
his most debasating attack. HEARTLESS ANGEL. When he
is flying higher get to the hi potion/elixer spot and
get to the part where it says Sora. Immeadiatly after
your hp and mp are gone use it. Then you must quickly
press triangle.The stage 1 routine happens now with the
new attacks.

Stage 3
Once 10 bars of health are gone the real fun starts.
You can tell Sephiroth is getting serious because a
purple outline appears.The only thing new is he will fly
around swinging his sword at you and uses a very difficult
to avoid attack that comes up at random attack called METEO.
When this happens he will become invincible and send meteors
crashing down on you. Just run around Sephiroth and you
shouldn't get to badly hert. Also you will need at least
one elixer/hi potion because his attacks are much faster and
unexpected in this stage. Just attack when he finishes a move
and you should win. You will get a Drive Gauge +1 when you
beat him.

Answer 2

Try gamefaqs.com here are some links

http://db.gamefaqs.com/console/ps2/file/kingdom_hearts_ii_sephiroth.txt

http://db.gamefaqs.com/console/ps2/file/kingdom_hearts_ii_sephiroth_a.txt