Requirements
Alignment: Any nongood.
Spell casting: Ability to cast 3rd level arcane or divine spells.
Skills: Knowledge (arcana) 8 ranks, Spellcraft 8 ranks.
Feats: Shadow Weave magic and any metamagic feat.

Class Skills
Bluff (Cha), Concentration (Con), Craft (Int), Disguise (Cha), Hide (Dex), Knowledge (all skills taken individually) (Int), Profession (Wis), Scry (Int), and Spellcraft (Int).
Skill Points at Each Level: 2 + Int modifier

Class Features
Weapon & Armor Proficiencies: Shadow adepts gain no proficiency in any weapon or armor.
Spells per Day: A shadow adept's training focuses on magic.  Thus, when a new shadow adept level is gained, the character gains new spells as if she also gained a level in whatever spell casting class she belonged to before he added the prestige class.  If the character has more than one spell casting class, they must decide to which class she adds the level of shadow adept for purposes of determining spells per day.
Shadow Feats: A shadow adept gains the Insidious Magic, Pernicious Magic, and Tenacious Magic feats.
Low-Light Vision: A shadow adept gains low-light vision if she doesn't already have it.
Shadow Defense: Add this value to the shadow adept's saving throws against spells from the schools of Enchantment, Illusion, and Necromancy, and spells with the darkness descriptor.
Darkvision (Su): A shadow adept can see in the dark as though she were permanently affected by a darkvision spell.
Metamagic Feat: The shadow adept can choose any one metamagic feat.
Spell Power: Add this value to the DC for saving throws and to caster level checks to overcome spell resistance for spells the shadow adept casts from the schools of Enchantment, Illusion, or Necromancy, and spells with the darkness descriptor.  This  stacks with other effects that affect the specified spells.
Shield of Shadows (Su): A shadow adept can create a mobile disk of purple-black force as a standard action.  The disk has the effect of a shield spell and provides three-quarters concealment (30% miss chance) against attacks from the other side of the shield.  The shield of shadows lasts for 1 round per caster level per day and need not be used all at once.  Creating or dismissing the shield of shadows is a standard action.  At 8th level, the shield also grants spell resistance of 12 + the characater's shadow adept level on attacks against the shadow adept that originate from the other side of the shield, as if the shadow adept were under the influence of a spell resistance spell.
Shadow Walk (Sp): A shadow adept can cast the shadow walk spell once per day.
Shadow Double: Once per day, a shadow adept can use a standard action to create a double of herself woven from shadowstuff.  The double has the ability scores , base AC, hit points, saves, and attack bonuses of its creator, but no equipment.  (Any apparent clothing or equipment is nonfunctional.)  The double can attack the creator's enemies if given a weapon or items (since it can use anything its creator can) or function as a target of a project image spell, duplicating the creator's  actions and acting as the origin of the creator's spells when it is within direct line of sight.  Mentally commanding the double is a free action.  Using it as the originator of a spell counts as an action for the creator and the double.  Causing the creator or double to leave the plane they share dismisses the double.  The double lasts 1 round per caster level.  The death of the double does not affect the shadow adept or vice versa.  The double still lasts to the end of its duration if its creator dies.