Full AI can be found here: Wiki link.

Overview

Stats

• Race: Aquatic, Insect
• Can be fully broken
• Resistance (no mods):

AI Summary

Overview

• Preemptive attack with 200% fire/light imperil
• Hit with fire/ice/light every turn to avoid DEF/SPR buff and ailment resist imperil
• Prepare resistance against Paralyze and Confusion
  (no need to stack active passive if hitting with boss's weakness every turn)
• Deals increased damage to non-human unit (a.k.a. Chow)
• Will use a lot of strong, magic attacks. No physical attacks are used.
• Boss will not imperil and do element damage on the same turn except on threshold.
• Every 3rd turn, boss will do a 90% AoE gravity move AND will keep attacking afterwards.
• Has DEF/SPR buffs that gets weaker over time.

Rotation

(Reset to T1 at 50% threshold.)

Above 50% HP:

• T1: AoE Paralyze/Confusion, AoE Non-elemental Magics
• T2: Strong ST Magic, 200% fire/light imperil, ATK/MAG break
• T3: AoE 90% Gravity, AoE 20k fixed damage, AoE Fire & Light magics

Under 50% HP:

• T1: AoE Paralyze/Confusion, AoE Fire & Light magics
• T2: AoE Non-elemental Magics, 200% fire/light imperil, ATK/MAG break
• T3: AoE 90% Gravity, AoE 20k fixed damage, AoE Fire & Light magics, AoE Non-elemental Magics

In addition, the boss may use more AoE/ST magics as remaining actions.

Team Building

General

• All 3 elements are viable.
• This is a magic tank survivability check. Invest in as much HP/SPR as possible.
• While you should not neglect resistance, it is not worth sacrificing stats to be fully immune due to the sheer amount of strong non-elem magic it does.
• Have a non-tank unit provoke. Your tank should still eat the magic attack, but they will have cover mitigation to help with surviving.
• The most dangerous turns are turn 1, where you don't have all buffs up, and turn 3 in the rotation due to the gravity attack.
• Prepare your best barrier skill for the gravity turns, as the barrier is not affected by gravity.
• Use Mechanical Heart (21O TMR) to your tank for healing if you can spare a slot.
• There are some RNG with the boss' remaining attacks.
• 'Dancing White Dragon', the card from Cleome's banner, may help with survivability.

Notable Units

Magic Tank

• Master Machinist Abigail: Obviously the best tank.
• Silent Knight Charlotte: Easy to gear, innate fire/light resist, 99% mag mit for turn 1, 75-85% insect mit, ATK/MAG break
• The Red Wings' Cecil: Innate fire/light resist, LB field, innate reraise
• Immortal Hyunckel: ATK/MAG break, light resist, bulky
• Some tanks like Solitary Patron Snow, Dynast-King's Scion Ashe, and even Beatrix has been used in clears, most likely with good external support.

Support

• Paladin Sylvie
• Al Bhed Girl Rikku: Massive barriers and heals, making it easier to bring weaker tanks.
• Reberta & Ignitos: Imperil cleanse, insect/aquan killer & mitigations, barrier on cooldown, LB fill, chain count
• Shrine Maiden Tsukiko: Imperil cleanse, fire/light imperil field, damage

Damage

• Flex: Skye, Samurai Chizuru, Beach Blaster Olive, Dark Mage Exdeath
• Fire: Lunar Festival Cleome
• Ice: Cheerful Caroler Ayaka, Frostblade Fryevia
• Light: 2B -Neo Vision-, A2 -Neo Vision-

Sample Teams (Rank 1, Max Mods)

More clears will be added according to comments. I will tag the reddit account of the Discord people if they let me know.

u/Minh-1987
Reberta & Ignitos / SK Charlotte / P Sylvie / SM Tsukiko / BB Olive / LF Cleome

u/Sinzar_
TRW Cecil / P Sylvie / ABG Rikku / 2B - NV- / Reberta & Ignitos / A2 -NV-
Reberta & Ignitos / SM Tsukiko / MM Abigail / BB Olive / S Chizuru / Any Unit
Dark Mage Exdeath / Any Unit / MM Abigail / Reberta & Ignitos / FB Fryevia / CC Ayaka

Kamikiro#7231 (Discord) (Youtube Link)
Reberta & Ignitos / SP Snow / P Sylvie / S Chizuru / SM Tsukiko / BB Olive

Rayster#6169 (Discord)
BB Olive / Serge / LF Cleome / Reberta & Ignitos / I Hyunckel / P Sylvie

u/Resnaught
2B / A2 / Tsukiko / Cleome / Reberta / Abigail
2B / Ayaka / Chizuru / Reberta / Sylvie / Cecil