How do you defeat sephiroth in kingdom hearts 2?

There are a few shortcut to defeating sephiroth. Here is a list of what you will need to have before you confront him at the Dark Depths.

  • Trinidy Limit
  • Thunder Boast
  • Magic Lock-on
  • High Jump
  • Arieal Dodge

  • Keyblade with highest strength (Oblivion, Ultima Weapon)
  • Various armor and accessories that boast strength and defense
  • 6 elixirs

  • Decent Strength
  • Decent Defense

  • Triangle - Elixir
  • Square - Thundaga

The first step is to Thunder him until your magic bar is almost empty. They Trinidy Limit him. Use Elixir. Repeat steps above in order.

Here is a list:
  1. Thundaga
  2. Trinidy Limit
  3. Elixir
  4. Repeat steps 1-3

CongGratulations! Talk to Cloud to claim you Fenrir.