Guide
How the kit works
Before combat, Overture of Inebriation creates a dimension for 15 seconds. Enemies inside follow Robin without attacking her. If you enter battle while it is active, she gains 5 Energy at the start of each wave. Only one allied Dimension Effect can exist at a time.
Robin's action advances by 25% when battle begins. Use Pinion's Aria to increase all allies' DMG by 50% for three turns; the duration decreases at the start of Robin's turns. The Skill also restores 5 Energy through a passive. Between refreshes, Wingflip White Noise deals Physical DMG equal to 100% of her ATK to one enemy.
Tonal Resonance gives all allies 20% CRIT DMG and restores 2 Energy to Robin after an ally attacks. Use Vox Harmonique, Opus Cosmique to enter Concerto and make every teammate except Robin act immediately. During Concerto, allies gain ATK equal to 22.8% of Robin's ATK plus 200. Each allied attack triggers Physical Additional DMG equal to 120% of her ATK, with fixed 100% CRIT Rate and 150% CRIT DMG. Follow-Up ATKs also gain 25% CRIT DMG.
Robin is immune to Crowd Control during Concerto, but cannot take a turn or act until it ends. A countdown with fixed 90 SPD appears in the Action Order; when its turn begins, Concerto ends and Robin acts immediately.
Build and why
For relics, start with four pieces of Musketeer of Wild Wheat: two give 12% ATK, while four add 6% SPD and 10% Basic ATK DMG. The ATK helps Robin's Ultimate buff and Additional DMG. Prisoner in Deep Confinement is another option: its two-piece bonus also gives 12% ATK. Its four-piece effect ignores 6% DEF per DoT on the target, up to three DoTs, so that part depends on the team.
For the planar set, Fleet of the Ageless gives Robin 12% Max HP and, at 120 SPD, gives all allies 8% ATK. Space Sealing Station instead gives Robin 12% ATK, plus another 12% at 120 SPD. Sprightly Vonwacq offers 5% Energy Regeneration Rate and advances her action by 40% on entering battle if she has 120 SPD.
Use ATK Percentage on the body and feet. The sphere can have ATK Percentage or Physical DMG Boost; the former also strengthens the Ultimate's ATK buff. Use Energy Regeneration Rate on the rope. For substats, look for ATK Percentage, then ATK, then SPD. Check the 120 SPD threshold if your planar set uses it.
Flowing Nightglow is the first weapon choice. Allied attacks build up to five stacks of Energy Regeneration Rate; using the Ultimate removes them and grants 48% ATK and 24% team DMG for one turn. But the Battle Isn't Over provides Energy Regeneration Rate and boosts the next ally's DMG after Robin uses her Skill. For Tomorrow's Journey gives ATK and increases Robin's DMG after her Ultimate.
Leveling priority
Follow the game's order: Vox Harmonique, Opus Cosmique first, then Pinion's Aria, Tonal Resonance, and Wingflip White Noise. The Ultimate supplies the team ATK buff and Additional DMG; the Skill and Talent strengthen team-wide bonuses. Basic comes last because its listed effect is single-target damage.
For maximum ascension, you need 308,000 Credit, 65 IPC Work Permit, and 15 each of Dream Collection Component, Dream Flow Valve and Dream Making Engine. For all skills, the materials are 3,000,000 Credit, 8 Tracks of Destiny, 18 Firmament Note, 69 Celestial Section, 139 Heavenly Melody, 12 Past Evils of the Borehole Planet Disaster, 41 Dream Collection Component, 56 Dream Flow Valve and 58 Dream Making Engine.
Eidolons worth it
For team support, I'd consider Land of Smiles first: it gives all allies 24% All-Type RES PEN during Concerto. Afternoon Tea For Two is another useful stop, adding 16% SPD during Concerto and raising the Talent's Energy recovery by 1 per trigger.
Moonless Midnight is an option if you want more damage from Robin herself. It increases the CRIT DMG of her Ultimate's Physical Additional DMG by 450%, up to eight triggers per Ultimate use. Raindrop Key instead dispels Crowd Control from all allies when she uses her Ultimate and gives them 50% Effect RES during Concerto.
You can stop at E1 or E2 if those team bonuses are enough for your build. Inverted Tuning and Lonestar's Lament raise skill levels rather than adding a separate effect. They are less interesting stopping points to consider, though you must pass them to reach later Eidolons.
Teams
Build around damage dealers who attack often, with a sustain character to keep the party alive. Every allied attack restores Energy to Robin, and attacks during Concerto also trigger her Additional DMG. Her passive CRIT DMG bonus for Follow-Up ATKs makes that attack type especially appealing.
Common mistakes
Do not expect Robin to refresh her Skill or use her Basic during Concerto. Check the Skill's remaining duration before entering it, since the buff counts down at the start of Robin's turns. Also pay attention to when teammates last acted: using the Ultimate after their actions can make better use of the immediate team advance.
Do not build only for Robin's Physical DMG. Her ATK also determines part of the team buff, while Energy Regeneration Rate helps her use the Ultimate. If you choose a planar bonus with a 120 SPD requirement, check her actual SPD rather than assuming the bonus is active. Her Technique's dimension also replaces any other allied Dimension Effect.
