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. She’s the Angel counterpart to Sonya Mainyu.

Biography
One of the super bosses in the Labyrinth of Chaos, Sonya Mazda is encountered as a 100th floor super boss. Like the other bosses of the Labyrinth, you can’t talk to her in battle; there is no rape scene upon being beaten by her.

Attacks

 * Holy Spear Dance – 4 Random Foes, Auto-Hit, Physical/Holy Attribute, Ascension 10%, 10 MP, 3 Turn Cooldown
 * Spiral Light Spear – All Foes, Auto-Hit, Physical/Holy Attribute, Ascension 10%, +200 Speed, 8 MP, 3 Turn Cooldown
 * Grand Cross – All Foes, Auto-Hit, Holy Attribute, Ascension 10%, 10 MP, 3 Turn Cooldown
 * Crystalline Breath – All Foes, Auto-Hit, Ice Attribute, Freeze 10%, 3 Turn Cooldown
 * Tidal Wave – All Foes, Auto-Hit, Water Attribute, 3 Turn Cooldown
 * Holy Flare – One Foe, Auto-Hit, Holy Attribute, Ascension 10%, 18 MP, 3 Turn Cooldown
 * Thunder of Judgement – One Foe, Auto-Hit, Lightning/Holy Attribute, Ascension/Shock 75%, 18 MP, 3 Turn Cooldown
 * Ahura Mazda – All Foes, Auto-Hit, Holy Attribute, Ascension 75%, 20 MP, 3 Turn Cooldown
 * Pleasure Eater – Self Buff, 3 Turns, Absorb Pleasure Damage, 3 Turn Cooldown
 * Unfathomable Nightmare – 4 Random Foes, Auto-Hit, Pleasure/Nightmare Attribute, 3 Turn Cooldown
 * Illusion Heaven Dance – Self Buff, 3 turns, +50% Atk/Agi/Phys.Eva, +200% Mag.Eva, +33% Auto Hit.Eva, +200 Accuracy, 4 MP, 3 Turn Cooldown
 * Madrain – One Foe, Magical, Non-Element MP damage, 100% MP Drain, 4 MP, 5 Turn Cooldown
 * Zero Shift – All Foes/All Allies, Auto-Hit, Dispel Foes, Resets Elemental and Stat Debuffs on Allies, 20 MP, 5 Turn Cooldown

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.