To cast a shapeshifter spell, you must have an Intelligence score of 10 + the spell's level. The Difficulty Class for a saving throw against a shapeshifter’s spell is 10 + the spell's level + the shapeshifter’s Int mod. Like other spellcasters, a shapeshifter can cast only a certain number of spells of each spell level per day. The base daily spell allotment is given in the table above. In addition, you receive bonus spells for a high Intelligence score. If you attempt to cast spells while wearing armor, you suffer an arcane spell failure chance.
A shapeshifter need not prepare spells in advance. You can cast any spell you know at any time, assuming you have not yet used up your spells per day for that level.
Attuning yourself to your aspect requires five minutes of meditation while you are in the aspected shape, during which you choose which augments to attune (much as a wizard prepares spells). If you cannot maintain the shape for at least five minutes, then you cannot select it as an aspect. You can attune a different aspect, or change the augments of your current aspect, as often as you wish, simply by spending another five minutes in meditation while in the appropriate shape. You can assume your aspect at any time as a free action. Likewise, you can suppress your aspect (losing the benefit of its augments and resuming your normal appearance) by concentrating as a standard action.
Augments come in five grades: least, lesser, greater, dark, and fearsome. At first, you can attune only a single aspect with least augments. As you advance in level, you gain additional aspects and can attune more powerful augments, as shown on Table: The Shapeshifter. However, you can only ever assume a single aspect at a time, and you must suppress your current aspect before you can assume a different one.
The number of augments you may attune at any one time is shown on Table: The Shapeshifter, above. If you can attune yourself to more than one aspect, you may attune up to your maximum number of augments separately for each one (e.g. a 10th-level shapeshifter can attune four least or lesser augments with his first aspect and four least or lesser augments with his second aspect, but must choose which aspect to assume at any given time).
When you reach 17th level, your body control becomes so impressive that you gain immunity to critical hits and stunning -- your system is simply too resilient to be crippled by a lucky strike.
This bonus increases to +4 at 13th level, and +6 at 17th level.
0 Level: detect magic (PH 219), read magic (PH 269), virtue (PH 298).
1st Level: accelerated movement (SC 7), aquatic escape (CS 95), aspect of the wolf (SC 16), babau slime (SC 22), beast claws (SC 25), beastland ferocity (SC 25), branch to branch (SC 38), camouflage (SC 43), claws of the bear (SC 47), climb walls (SC 47), cobra’s breath (CArc 1010), ease of breath (SC 93), endure elements (PH 226), enlarge person (PH 227), expeditious retreat (PH 228), expeditious retreat, swift (SC 85), feather fall (PH 229), fist of stone (SC 94), jump (PH 246), longstrider (PH 249), magic fang (PH 250), nerveskitter (SC 146), ram’s might (SC 166, rapid burrowing (SC 166), reduce person (PH 269), remove scent (SC 173), scales of the lizard (CArc 121), spider form, lesser (DotU 63), webfoot (Storm 125), winged watcher (CS 106), wings of the sea (SC 240).
2nd Level: alter self (PH 197), animalistic power (Ph2 101), balancing lorecall (SC 23), balor nimbus (SC 28), barkskin (PH 203), bear’s endurance (PH 203), belker claws (SC 26), blinding spittle (SC 32), body of the sun (SC 35), bull’s strength (PH 207), burrow (SC 41), camouflage, mass (SC 43), cat’s grace (PH 208), discern shapechanger (SC 66), eagle’s splendor (PH 225), extend tentacles (SC 86), false life (PH 229), fearsome grapple (SC 90), fins to feet (SC 92), fox’s cunning (PH 233), fuse arms (SC 100), heart of air (CM 106), jaws of the moray (Storm 117), kuo-toa skin (Storm 118), listening lorecall (SC 133), metal fang (CC 124), owl’s wisdom (PH 259), primal hunter (DrM 71), quickswim (Storm 120), razorfangs (Dr 80), reduce animal (PH 269), scintillating scales (SC 181), spider climb (PH 283), swim (SC 217), tiger’s tooth (SC 221), tojanida sight (Storm 123), urchin’s spines (Storm 124), wings of air (SC 240).
3rd Level: air breathing (SC 8), amorphous form (SC 8), arcane sight (PH 201), bite of the wererat (SC 28), charge of the triceratops (SC 45), dispel magic (PH 223), dragonskin (SC 73), ferocity of sanguine rage (DrM 67), fire wings (SC 93), forestfold (SC 98), gaseous form (PH 234), girallon’s blessing (SC 106), hamatula barbs (SC 109), heart of water (CM 107), jagged tooth (SC 126), lion’s charge (SC 133), magic fang, greater (PH 250), primal form (SC 161), primal instinct (DrM 72), quill fire (SC 164), scales of the sea lord (Storm 121), shape of the hellspawned stalker (CM 117), sharptooth (SC 187), snakebite (SC 193), spider form (DotU 63), thornskin (SC 219), tremorsense (SC 224), unicorn horn (CM 121), vision of the omniscient eye (DrM 74), water breathing (PH 300).
4th Level: aboleth curse (Storm 113), aspect of the icy hunter (CM 96), bite of the werewolf (SC 29), burning blood (SC 40), burrow, mass (SC 41), corporeal instability (SC 53), displacer form (SC 67), dragonshape, least (DrM 66), enlarge person, mass (PH 227), essence of the raptor (SC 84), fangs of the vampire king (SC 88), flame whips (SC 95), flight of the dragon (SC 95), giant vermin PH 235), heart of earth (CM 106), magic fang, superior (SC 136), passage of the shifting sands (DrM 70), primal senses (DrM 72), reduce person, mass (PH 269), sandform (Sand 119), skin of the cactus (Sand 120), stoneskin (PH 284), swim, mass (SC 217), tenser’s transformation (PH 294), trollshape (PH2 127), wild runner (SC 239), wind at back (SC 239), wings of air, greater (SC 240).
5th Level: animal growth (PH 198), baleful polymorph (PH 202), bite of the wereboar (SC 28), blood creepers (PH2 104), break enchantment (PH 207), draconic might (SC 72), dragonsight (SC 73), dridershape (DotU 61), enlarge person, greater (SC 82), flaying tendrils (CM 104), flesh to ice (Frost 94), form of the desert hunter (DrM 67), form of the threefold beast (CM 105), gutsnake (SC 108), heart of fire (CM 107), ice to flesh (Frost 100), metal skin (CArc 115), nightstalker’s transformation (SC 148), plant body (SC 159), poison thorns (SC 159), polymorph (PH 263), quill blast (SC 164), reduce person, greater (SC 171), sirine’s grace (SC 191), spider form, greater (DotU 63), transformation of the deeps (Storm 123), unicorn blood (CM 11).
6th Level: animalistic power, mass (PH2 101), aspect of the earth hunter (SC 16), bear’s endurance, mass (PH 203), bite of the weretiger (SC 28), bull’s strength, mass (PH 207), cat’s grace, mass (PH 208), chasing perfection (PH2 106), cloak of the sea (SC 48), dispel magic, greater (PH 223), dragonshape, lesser (DrM 66), eagle’s splendor, mass (PH 225), flesh to stone (PH 232), fleshshiver (SC 95), fox’s cunning, mass (PH 233), owl’s wisdom, mass (PH 259), primal speed (DrM 72), stone body (SC 207), stone to flesh (PH 285), tortoise shell (SC 221), true seeing (PH 296), wooden blight (CC 130).
7th Level: adamantine wings (CM 95), arcane sight, greater (PH 201), avasculate (SC 19), bite of the werebear (SC 28), blood to water (SC 33), body of war (SC 35), body outside body (CArc 100), draconic polymorph (Dr 79), giant size (CArc 109), kiss of the vampire (SC 128), nixie’s grace (SC 148), unicorn heart (CM 121).
8th Level: animal shapes (PH 198), avascular mass (SC 19), bite of the king (SC 28), dreaded form of the eye tyrant (CM 102), elemental body (SC 78), flensing (SC 95), ghostform (SC 103), iron body PH 245), megalodon empowerment (Storm 118), minute form (CArc 115), unyielding form of inevitable death (CM 122).
9th Level: arboreal transformation (CM 95), cast in stone (SC 43), dragonshape (PH2 111), shapechange (PH 277).