Sonya Mazda/Labyrinth of Chaos

Sonya Mazda (ソニアマズダ, Sonia Mazuda) is a super boss encountered in the Labyrinth of Chaos. You cannot talk to her and there’s no rape scene if you’re beaten by her. She’s the angelic counterpart to Sonya Mainyu.

Attacks

 * Holy Spear Dance – 4 Random Foes, Auto-Hit, Physical/Holy Attribute, Ascension 10%, 3 Turns Cooldown, 10 MP
 * Spiral Light Spear – All Foes, Auto-Hit, Physical/Holy Attribute, Ascension 10%, +200 Speed, 8 MP
 * Grand Cross – All Foes, Auto-Hit, Holy Attribute, Ascension 10%, 10 MP
 * Crystalline Breath – All Foes, Auto-Hit, Ice Attribute, Freeze 10%,
 * Tidal Wave – All Foes, Auto-Hit, Water Attribute
 * Holy Flare – One Foe, Auto-Hit, Holy Attribute, Ascension 10%, 18 MP
 * Thunder of Judgement – One Foe, Auto-Hit, Lightning/Holy Attribute, Ascension/Shock 75%, 18 MP
 * Ahura Mazda – All Foes, Auto-Hit, Holy Attribute, Ascension 75%, 20 MP
 * Pleasure Eater – Self Buff, 3 Turns, Absorb Pleasure Damage,
 * Illusion Heaven Dance – Self Buff, 3 Turns, +50% Agility, +100% Magic Evasion, +100% Hit-Rate, 4 MP
 * Zero Shift – All Foes, Auto-Hit, Dispel, 5 Turns Cooldown, 20 MP

Strategy
Fight her like you would deal with any of the Labyrinth of Chaos bosses:
 * Always have Vicarious Clara active or another barrier active. One of her attack hits 4 random times, so stacking buffs is recommended.
 * Anti-Death Song (Kitsune Geisha only) is needed to counter the Ascension effect on Her holy attacks.
 * She possess a buff increasing her Agility and Evasion, and another one making her resistant to Pleasure. Dispel is recommended to stay able to attack her.
 * She also possess a Freeze attack, which can be countered with the Resist Freeze ability owned by Sea Palace Maikos, making them useful. Additionally, she can be Slowed/Stopped by the Time Warp Dance and her resistances can be debuffed by the Sea Palace Maiko’s skills.
 * Finally, she has a skill which inflicts a single target Shock, that can be resisted by the Battle Master Resist Shock ability, allowing you to keep your damage output.

Overall, her greatest strengths come from her extremely high resistances, making her immune to most damaging attacks until debuffed.

Check here and here for detailed information on all the super bosses and everything you can make use of to defeat them.

A battle against her with only Part 1 equipment, no Crisis Hairpin and no stats upgraded can be seen here.