Something relatively conventional for once: a fiendish bronze dragon, albeit using some feats from the Draconomicon. Thanks to CRGreathouse's dragon generator for doing most of the hack work.
Malentha: fiendish female young adult bronze dragon; CR 12; Large Dragon (water, spirit); HD 18d12+72 (200 hp); Init +4; Spd 40 ft, fly 150 ft (poor), swim 60 ft; AC 26 (touch 9, flat-footed 26); BAB +23; Grap +28; Atk +23 melee (2d6+6, bite) and +18/+18 melee (1d8+3, 2 claws) and +18/+18 melee (1d6+3, 2 rear claws) and +18 melee (1d8+9, tail slap); S/R 10 ft/5 ft (10 ft with bite); SA Breath weapon, frightful presence, spell-like abilities, spells; SQ Alternate form, blindsense 60 ft, DR 10/magic, darkvision 120 ft, electricity immunity, cold and fire resistance 10, SR 23; AL CE; SV Fort +15, Ref +11, Will +15; Str 23, Dex 10, Con 19, Int 18, Wis 19, Cha 18.
Skills and Feats: Bluff +11, Concentration +23, Diplomacy +27, Listen +23, Spot +23, Flyby Attack, Heighten Breath, Improved Initiative, Power Attack, Recover Breath, Shape Breath, Wingover.
SA — Breath Weapon (Su): 80-ft line (40-ft cone if shaped), 10d6 electricity, Reflex DC 23 half (or higher if heightened); or 40-ft cone (80-ft line if shaped) repulsion 1d6+5 rounds, Will DC 23 negates (or higher if heightened).
SA — Frightful Presence (Ex): 150 foot radius, 17 HD or fewer, Will DC 23 negates.
SA — Spell-Like Abilities: At will — speak with animals. Caster level 5th.
SQ — Alternate Form (Su): Malentha can assume any humanoid form of Medium size or smaller as a standard action 3 times per day. This ability functions as a polymorph spell cast by a 5th level sorcerer, except that she does not regain hit points for changing form and can only assume the form of a humanoid. Malentha can remain in her humanoid form until she chooses to assume a new one or return to her normal form.
Spells Per Day (6/7/5; save DC = 14 + spell level): 0 — dancing lights, detect magic, mage hand, mending, ray of frost, read magic; 1st — bless, shield, true strike; 2nd — blur, cure moderate wounds.
Malentha: fiendish female young adult bronze dragon; CR 12; Large Dragon (water, spirit); HD 18d12+72 (200 hp); Init +4; Spd 40 ft, fly 150 ft (poor), swim 60 ft; AC 26 (touch 9, flat-footed 26); BAB +23; Grap +28; Atk +23 melee (2d6+6, bite) and +18/+18 melee (1d8+3, 2 claws) and +18/+18 melee (1d6+3, 2 rear claws) and +18 melee (1d8+9, tail slap); S/R 10 ft/5 ft (10 ft with bite); SA Breath weapon, frightful presence, spell-like abilities, spells; SQ Alternate form, blindsense 60 ft, DR 10/magic, darkvision 120 ft, electricity immunity, cold and fire resistance 10, SR 23; AL CE; SV Fort +15, Ref +11, Will +15; Str 23, Dex 10, Con 19, Int 18, Wis 19, Cha 18.
Skills and Feats: Bluff +11, Concentration +23, Diplomacy +27, Listen +23, Spot +23, Flyby Attack, Heighten Breath, Improved Initiative, Power Attack, Recover Breath, Shape Breath, Wingover.
SA — Breath Weapon (Su): 80-ft line (40-ft cone if shaped), 10d6 electricity, Reflex DC 23 half (or higher if heightened); or 40-ft cone (80-ft line if shaped) repulsion 1d6+5 rounds, Will DC 23 negates (or higher if heightened).
SA — Frightful Presence (Ex): 150 foot radius, 17 HD or fewer, Will DC 23 negates.
SA — Spell-Like Abilities: At will — speak with animals. Caster level 5th.
SQ — Alternate Form (Su): Malentha can assume any humanoid form of Medium size or smaller as a standard action 3 times per day. This ability functions as a polymorph spell cast by a 5th level sorcerer, except that she does not regain hit points for changing form and can only assume the form of a humanoid. Malentha can remain in her humanoid form until she chooses to assume a new one or return to her normal form.
Spells Per Day (6/7/5; save DC = 14 + spell level): 0 — dancing lights, detect magic, mage hand, mending, ray of frost, read magic; 1st — bless, shield, true strike; 2nd — blur, cure moderate wounds.