Alternate costumes...
	Legend Of Zelda reference...
	Master Ninja Difficulty...
	Shadow of the Warrior Bonuses...

How to unlock alternate costumes for Ryu, Ayane & Momiji. You can only obtain Crystal Skulls on Normal or higher difficulty, also you only need to pick up the Crystal Skull to unlock Ryu & Ayane's 4th costume.

Costume	How to unlock
Kasumi's 3rd costume	Beat 25 Ninja Trials.
Kasumi's 4th costume	Beat 50 Ninja Trials.
Momiji 3rd costume	Complete 25 Ninja Trials with Momiji.
Momiji 4th costume	Complete 50 Ninja Trials total with Momiji.
Ryu & Ayane 3rd costume	Collect all 50 scarabs.
Ryu & Ayane 4th costume	Collect all 10 Crystal Skulls.

Near the first save point in level 1, go to the gate to the left of the red bus, The Triforce crest from the Legend Of Zelda series is engraved on the gate.

Beat the game on the Hard difficulty setting to unlock the Master Ninja Difficulty setting which is a lot tougher.

The following effects become available for online play when you complete the corresponding task.

Adept Armour:
Reach Player Level 3

Adept Headgear:
Reach Player Level 3

Bandage Armour:
Successfully betray your team 1 time in Clan Battle

Black Spider Armour:
Clear 1 Ultimate Ninja Trial

Black Spider Headgear:
Clear 1 Ultimate Ninja Trial

Colour: Amaranth:
Reach Player Level 50

Colour: Ash:
Reach Player Level 5

Colour: Blood:
Reach Player Level 25

Colour - Earth:
Reach Player Level 2

Colour - Fire:
Reach Player Level 20

Colour - Forest:
Reach Player Level 35

Colour - Ice:
Reach Player Level 10

Colour - Sand:
Reach Player Level 15

Colour - Sky:
Reach Player Level 40

Colour - Toad:
Reach Player Level 30

Colour - Twilight:
Reach Player Level 45

Crest Headgear:
Clear 10 Acolyte Ninja Trials

Crimson Demon Armour:
Win 1 Team Battle in Clan Battle

Crimson Demon Headgear:
Win 2 Team Battles in Clan Battle

Dark Ninja Armour:
Clear 3 Ultimate Ninja Trials

Dark Ninja Headgear:
Clear 3 Ultimate Ninja Trials

Dark Wings Headgear:
Clear 5 Mentor Ninja Trials

Hanya Headgear:
Clear 5 Leader Ninja Trials

Hyottoko Headgear:
Clear 1 Master Ninja Trial

MagojiroHeadgear:
Clear 3 Master Ninja Trials

Mentor Armour:
Reach Player Level 6

Mentor Headgear:
Reach Player Level 6

Nioh Headgear:
Clear five Master Ninja Trials

Okame Headgear:
Clear two Master Ninja Trials

Old Man Armour:
Kill one leader in Clan Battle

Old Man Headgear:
Kill 2 leaders in Clan Battle

Power Up: Arrows +2:
Reach Player Level 8, 12, 17, or 22

Power Up: Shuriken +4:
Reach Player Level 9, 13, 18, 23

Regent Armour:
Clear 2 Ultimate Ninja Trials

Regent Headgear:
Clear 2 Ultimate Ninja Trials

Scarlet Headgear:
Clear 1 Mentor Ninja Trial

Shuriken Headgear:
Clear 10 Mentor Ninja Trials

Tengu Headgear:
Clear 4 Master Ninja Trials

Three Strokes Headgear:
Clear 5 Acolyte Ninja Trials

Trainee Headgear:
Clear 1 Leader Ninja Trial

Wanderer Armour:
Win 1 Battle Royale in Clan Battle

Wanderer Headgear:
Win 2 Battle Royales in Clan Battle

White Fox Headgear:
Successfully betray your team 2 times in Clan Battle