Spirit Stones produce effects based on battle actions. That official description makes them build connectors: each Stone rewards a condition, so its value depends on how often Emma and Koo perform that condition and whether the result advances the build’s job. A Stone should be chosen from observed trigger frequency, not its name or assumed rarity.
This page is about composing a loadout. The Spirit Stone gear reference is where individual names, acquisition locations, and exact live descriptions belong after launch.
Translate the description into a test
Read the in-game text literally. Separate the trigger, target, result, duration, limit, and any cooldown or stack language. If a Stone activates after a successful parry, the test needs the game’s parry feedback. If it mentions Down, distinguish buildup from the vulnerable state or conversion. If it names a Bloom Art, use the same Art and FP start.
Do not fill missing details from the icon. Record “not stated” when the description omits a value, then observe the result under controlled conditions. A clear unknown is better than a false percentage.
Match trigger frequency to playstyle
Aggressive Emma may perform close attacks and parries frequently, making action-linked effects easier to maintain. A ranged setup may value distance or projectile-related triggers but activate close-defense conditions less often. A stealth-first setup may have a powerful opener condition and little uptime after detection.
Koo’s Art cadence also matters. A Stone tied to command use needs enough FP generation to activate. Count actual successful parries and Arts per encounter. Build for the player’s repeatable rhythm, not an idealized perfect run.
Assign every slot a role
Give each Stone one reason to exist: survival, FP access, health damage, Down buildup, conversion, control, or movement. Two effects can work together when one creates the condition for another. They can also compete if both require mutually exclusive actions or if the game applies a cap.
Start with one Stone, verify it, then add another. If the combined result differs, investigate stacking order, caps, target state, and timing. The public UI must establish the number of slots, unlock progression, duplicate rules, and removal cost; none should be assumed from pre-launch imagery.
Build around a parry-to-command chain
One coherent concept begins with Emma’s successful parry, which generates FP. A Stone can improve a confirmed part of that chain only if its final text says so. Koo then spends FP on a Bloom Art, and Emma converts the effect into health or Down pressure.
Test the entire sequence. Record the FP before and after defense, Stone cue, Art cost, Art result, and Emma follow-up. This prevents crediting the Stone for a value actually produced by a skill, Charm, difficulty rule, or the Art itself.
Build around Down conversion
Another concept prioritizes reaching the Down state and using its opening. Select Stones whose final triggers support the buildup or payoff, then compare against the same durable enemy. Count repeatable actions to Down and whether Emma was in position to convert.
Do not combine health damage and Down into one score. A setup may reach the opening faster but deal less ordinary damage, or the reverse. Choose based on encounter objective and reliability, and attach the version because balance changes can shift both.
Measure uptime instead of tooltip excitement
For an effect with a visible duration, record activation count, total active time, and whether the build used the benefit. For an immediate effect, count valid triggers and outcomes. Compare over several encounters rather than one favorable sequence.
An effect that is active often but does not alter a meaningful result can still be low value. Conversely, a rare effect that consistently saves a boss phase may justify the slot. Uptime is evidence, not the entire decision.
Prevent hidden-variable comparisons
Keep difficulty, enemy, weapon, Emma skills, Koo Charm and Arts, and visible version fixed. Remove edition items from one trial only if they alter the tested condition. Story’s forgiving parry window can increase trigger frequency, so do not apply a Story result to Hard without a new sample.
Capture the UI cue for activation and the final loadout screen. If a patch changes wording, retest instead of preserving an old effect under a new description.
What is confirmed before release
The existence and battle-action basis of Spirit Stones appear in first-party descriptions on the Steam Store and publisher materials. The official Developer_Direct article provides the duo combat context. No full official Stone catalog, slot count, stacking rule, or numerical effect set was public on 2026-08-01; those details require direct AppID 2001760 evidence.