Successfully complete the game under the normal difficulty setting.

Hold L2 while watching an intermission sequence from the "Encyclopedia" screen to see Ayame or Rin with their armor.

Hold L1 and select the "Tutorial" option.

The following Two weapons can be unlocked by first finding them while in Story Mode. There is one unlockable weapon for each character. Once you have the weapons and complete the missions they will always be available in your Item Selection Screen.

In Chapter 7.1 or 7.2 of story mode, get to the room across from the Boss battle room. Note: Do not use the shortcut, or this room will be sealed.

Complete Chapter 10-1 or 10-2 with a "Grandmaster" rank in Level Select mode.

Complete Chapter 12-1 or 12-2 with a "Grandmaster" rank in Level Select mode.

Complete Chapter 11 with an "Assassin" rank in Level Select mode.

In Chapter 8 of story mode, cross the bridge then move left along the wall. Double jump over to the little outcropping/ledge to find it.

Complete Chapter 9 with a "Assassin" rank in Level Select mode.

Collect the indicated number of scrolls in story mode to unlock the corresponding special ability.

Arrow Block: 250 (Ayame) or 30 (Rin)
Cheetah Sprint: 150 (Ayame)
Crescent Moon: 30 (Ayame)
Crimson: 200 (Rin)
Crimson Final: 550 (Rin)
Death Drop: 60 (Rin)
False Wall: 500 (Ayame)
Fang Guard: 10 (Rin)
Hawk Eye: 60 (Ayame) or 150 (Rin)
Inner Ear: 200 (Ayame)
Long Claw: 300 (Ayame) or 350 (Rin)
Mimicry: 500 (Rin)
Mind Control: 400 (Ayame)
Numbing Strike: 250 (Rin)
Shadow: 300 (Rin)
Sniper: 350 (Ayame) or 450 (Rin)
Spider's Nest: 450 (Ayame) or 400 (Rin)
Swift Guard: 100 (Ayame)
Wall Run: 10 (Ayame) or 100 (Rin)
Wrath: 550 (Ayame)