Guide
How the kit works
Start with Waveshock when Rover enters the fight. It deals Spectro DMG and grants Diminutive Sound. Land attacks from Vibration Manifestation to build more. Heavy Attack: Aftertune (basic) also grants Diminutive Sound when it hits.
After the third Basic Attack or a Heavy Attack, press Basic Attack at the right time for Heavy Attack: Resonance (basic). Silent Listener gives Rover 15% ATK for 5 seconds when this attack is cast. If it hits, press Basic Attack again for Heavy Attack: Aftertune. You can also use Aftertune after a Dodge Counter hits.
World in a Grain of Sand holds up to 100 Diminutive Sound. When you have more than 50, casting Resonating Slashes spends 50 and uses Resonating Spin (forte) instead. Press Basic Attack after the spin ends for Resonating Echoes (forte). Both attacks deal Spectro DMG counted as Resonance Skill DMG; Reticence (passive) increases the follow-up’s damage by 60%.
Use Echoing Orchestra for delayed area damage. When you switch out, Instant creates a stasis area around the incoming Resonator for 3 seconds.
Build and why
Celestial Light is the first set to consider for damage: its two-piece effect gives 10% Spectro DMG. Moonlit Clouds is another option when you want Energy Regen, with 10% from two pieces. The game recommends five pieces of Eternal Radiance; its listed two-piece effect also gives 10% Spectro DMG.
Emerald of Genesis is the first weapon choice. It gives 12.8% Energy Regen, and casting a Resonance Skill grants 6% ATK for 10 seconds, stacking up to twice. Blazing Brilliance is another strong option for the empowered skill sequence: it gives 12% ATK and builds stacks that each add 4% Resonance Skill DMG Bonus, up to 14 stacks. Casting a Resonance Skill grants five stacks.
For a 4-star option, Lunar Cutter gives six Oath stacks on entering the field, each adding 2% ATK. It loses one stack every 2 seconds. Endless Collapse is another option: casting a Resonance Skill grants 6 Resonance Energy and 10% ATK for 16 seconds, with a 20-second trigger interval.
Consider ATK and Crit. Rate for damage, and Energy Regen when you need more access to Liberation. Rover’s fourth node also describes healing based on ATK, although its skill name needs checking against the listed Liberation.
Leveling priority
As a suggested order, level World in a Grain of Sand first for the empowered skill sequence, then Resonating Slashes for the forward attack. Follow with Echoing Orchestra for its area damage, Vibration Manifestation for the attacks you use to build Diminutive Sound, and Waveshock last.
For maximum ascension, you need 170,000 Shell Credit, 4 LF Whisperin Core, 12 MF Whisperin Core, 12 HF Whisperin Core, 4 FF Whisperin Core, 5 Mysterious Code and 60 Pecok Flower.
To max all skills, you need 2,030,000 Shell Credit, 25 LF Whisperin Core, 28 MF Whisperin Core, 40 HF Whisperin Core, 57 FF Whisperin Core, 26 Unending Destruction, 25 Inert Metallic Drip, 28 Reactive Metallic Drip, 55 Polarized Metallic Drip and 67 Heterized Metallic Drip.
Resonance Chain nodes worth it
Echoes of Wanderlust (sequence 6) is a good goal for a Spectro team. Resonating Slashes and Resonating Spin (forte) reduce the target’s Spectro RES by 10% for 20 seconds when they hit.
Odyssey of Beginnings (sequence 1) is a useful early damage option: casting either of those skills gives Rover 15% Crit. Rate for 7 seconds. Microcosmic Murmurs (sequence 2) is worth considering for its 20% Spectro DMG Bonus.
Resonating Lamella (sequence 4) describes team healing equal to 20% of Rover’s ATK every second for 5 seconds. Its description calls the Liberation Echoing Resonance, while the listed skill is Echoing Orchestra. Check the in-game description before relying on the heal.
If you are stopping partway through the chain, Visages of Dust (sequence 3) is less appealing when you already have enough Energy Regen. You can also leave Temporal Virtuoso (sequence 5) alone if the 40% Resonance Liberation DMG Bonus is not what you need.
Teams
Phoebe and Zani are Spectro teammates named in the guides. They can benefit from the Spectro RES reduction once Rover has the sixth node. Apply it by hitting the target with the regular or empowered Resonance Skill.
Verina and Shorekeeper are other Spectro options named in the guides. Ciaccona is an Aero option if you want a different element. Check what the rest of your team needs, including healing, before choosing the remaining slots.
Rover contributes on-field damage and a 3-second stasis area for the incoming character. Before the sixth node, do not count on Rover to reduce Spectro RES.
Common mistakes
Do not cast the skill expecting the empowered version at exactly 50 Diminutive Sound. The stated requirement is more than 50. After the spin, remember to press Basic Attack for the follow-up rather than switching out immediately.
Do not treat the follow-up as ordinary Basic Attack damage just because it uses the Basic Attack button. It counts as Resonance Skill DMG, which is why Blazing Brilliance is relevant. The spin has the same damage classification.
Do not miss Heavy Attack: Resonance (basic) if you want the ATK increase from Silent Listener. Time the Basic Attack input after the third Basic Attack or a Heavy Attack, then follow a hit with Heavy Attack: Aftertune (basic) for more Diminutive Sound.