Inuyasha: Feudal Combat

Secret trailer:
Hold L1 + R1 + Triangle at the main menu to unlock an option to play the secret trailer.

Miroku and Sango's Chapter:
Complete Inuyasha's Chapter in story mode.
Wurd.

Sesshomaru's Chapter:
Complete Miroku's Chapter in story mode.
eisdeia imemyftlWurd.

Shippo's Chapter:
Complete Sesshomaru's Chapter in story mode.
Wurd.

Play as Naraku:
Complete Inuyasha's Chapter in story mode without using any continues.
Wurd.

Play as Bankotsu:
Complete Miroku's Chapter in story mode without using any continues.
Wurd.

Play as Demon Inuyasha:
Complete Sesshomaru's Chapter in story mode without using any continues.
Wurd.

Play as Human Inuyasha:
Complete Shippo's Chapter in story mode without using any continues.
Wurd.

Naraku's Castle level:
Successfully complete mission mode.

Challenging mode:
Successfully complete mission mode with three different characters.

Hint: Team attacks:
You and a partner can pull off some devastating attacks. To pull off a team attack, press X + Square. To pull off a team combo special, press Circle after you have leveled up twice. Your partner will glow red when you are able to perform a team combo special. Remember, both of these team attacks take a level from your Spirit Force meter when used.
Wurd.

Hint: Devastating team finishing moves:
In order to do this move, you and your team member must have a match up level to great. It is better to set your member with the red icon so that you can get that match level great faster. When they are glowing red, press Circle to do the finishing team attack. Note: Only these character teams will show their unique attacks, and the order does not matter: Inuyasha and Kagome, Inuyasha and Kikyo, Inuyasha and Sesshomaru, Kagome and Kikyo, Sango and Miroku.
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Hint: Hidden cover:
Remove the game's cover from the slipcase. The reverse side contains an alternate version of it.
randy Strang.

Glitch: Leave level boundary:
Select Sesshomaru and go to Dark Pearl level. Jump off the stage and wait for the bird to drop you off. Then, after you jump off the bird, do the midair X attack. You will go so far that you will be in the background area, but still be able to walk around.
csh1111 via Wurd.

Glitch: Flying Sesshoumaru:
Go to the Black Pearl level (with the giant skeleton dog in the background). Jump off the edge with Sesshoumaru. When the bird carries you back, do the X midair attack. You will fly offstage, but still be able to walk.
WebMaster CJ.

Play as Sesshoomaru with a fast character (Shippoo, etc.) as an opponent. As soon as the fight begins, have the opponent chase you off the edge. When the bird carries you back to the stage, use an aerial attack with perfect timing. You will not be on the platform, but will instead be walking in mid-air temporarily. This will work also you if you do the same thing, except you can play as fast character, such as Shippoo, and run Sesshomaru off the edge. When the bird brings Sesshoomaru back, attack with an aerial attack. He might counterattack with an aerial, and Sesshoomaru will end up walking in mid-air. This will work best with Shippoo.
OkamiZaku.

Play as Sesshoomaru. Fight at the Black Pearl stage. Run straight to your opponent and fall of the stage. When the bird retrieves you, use a midair attack. You will be able to walk around, and yet you do not fall unless you try to get back up to the stage. This also works with Inuyasha, but it will be a lot more difficult and you must have an opponent that is not Sesshoomaru or Naraku. Also, you must not use a sword/midair attack while on the retrieving bird.
OkamiZaku.