Beast of Reincarnation Spirit Stones — Best Picks & Slots
Updated September 9, 2026 · Facts cross-checked against the sources listed below
How Spirit Stone Slots Work
- Emma has up to 6 stone slots — but the number you can actually use is set by your equipped armor. When comparing pieces, check slots as well as defense: a lower-defense piece with more slots often wins. Only four armor pieces reach the full six, and the earliest is available in Chapter 3 — the armor guide lists slot counts for all 14.
- Stones are Emma’s system. Koo uses a separate one: charms, of which he wears exactly one. Don’t plan a build around stacking both on the same character.
- Loadouts can be swapped freely outside combat at no cost — which is exactly why endgame play revolves around re-stoning before each boss.
Where Stones Come From
- Strongboxes and chests across every region (see strongbox codes).
- Brad’s shop on the Cleanse Walker, for Amber.
- Calculations research at the Cleanse Walker can duplicate a stone you already own — the intended way to double up a favorite.
- Unidentified “?” stones reveal themselves when you rest at a campsite — the same mechanic that identifies Koo’s Decayed Charms.
- Withered Beasts in the Crater Zone (Chapter 8) drop high-tier stones, and they respawn on rest — the most efficient late-game source, and the same loop most guides recommend for levelling.
The Stones Worth Slotting
| Stone | Effect | Why It’s Good |
|---|---|---|
| Homing Shots | Ranged attacks track targets | Core stone of every endgame element build |
| Onslaught | Vigor (attack) boost at battle start | Front-loads burst damage |
| Fortification | Fortitude (defense) boost at battle start | Tank/sustain sets |
| Momentum | Emma at full HP: +6% ATK for Emma and Koo | Rewards clean parry play |
| Critical Mind | Higher crit rate while recovering | Pairs healing with damage windows |
| Sharpshooter | Weak-point hits restore resources | Ranged-hybrid loops |
| Entanglement Parry / Dodge | Gauge charge on parry / dodge | Feeds Blade Arts faster |
| Critical Damage Increase | Bigger crit hits | Stacks with Critical Mind |
| Florescent Recovery | Improved healing | Comfort pick for long fights |
Synergy Sets by Playstyle
- Crit-execution: Critical Mind + Onslaught + a Fang-line Skill Amber (Binding or Destructive Fang) — stack crits into Down Gauge executions.
- Tank & sustain: Fortification + Golem Incense + a control Fang — for learning hard bosses.
- Element/status: Entanglement stones + a Fang matching your element — the backbone of the Shock / Poison / Acid endgame builds.
- Ranged hybrid: Homing Shots + Sharpshooter + Archery Incense — sustain ammo through weak-point hits.
Skill Ambers (Koo’s equivalent slot items) split into two lines: Fang for offense and Incense for support — match them to the same plan as Emma’s stones.
Per-Boss Swapping
The endgame loop is simple: check the next Nushi’s element and attack pattern (see the boss guide), re-stone for it, and swap Koo’s Charm and Bloom Art to match. Nothing is consumed by swapping, so there’s no reason to run one static set past the mid-game.
Patch Notes That Touch Spirit Stones
Two official fixes, so you know what was a bug and what was not. Patch 1.0.9 (August 24) made the equipment screen show which Spirit Stone effects are active, and fixed a case where re-equipping a stone to the same slot could silently unequip stones in other slots. Patch 1.0.11 (September 8) adds: “Fixed an issue where the quantity and sell price for Spirit Stones were incorrectly displayed.” So if a vendor screen on 1.0.10 or earlier showed a stone count or price that did not match your inventory, that was the display, not your stones — the numbers were wrong, the items were not. Full patch history on the patch notes page.