git:20260913.ed0ec2c to git:20261002.615add9

6 added, 0 removed. Audit A to A.

---

name: juice-vfx

description: Use when authoritative gameplay events need flashes, particles, trails, hit sparks, screen/camera accents or other runtime VFX presentation that must not own damage, hitboxes, timing or simulation.

---

# Juice and VFX

This skill owns runtime **presentation** effects. Asset generation belongs to `vfx-generate`; gameplay state remains authoritative in its domain owner.

## Compatible modes

| Mode | Presentation density |

|---|---|

| dry | minimal/no optional VFX |

| punchy | selected short accents |

| maximal | richer authored layers within performance/accessibility budgets |

## Event contract

Each effect binds to an authoritative event/state ID and declares spawn anchor, lifetime/end condition, stacking/retrigger policy, ownership/cleanup, performance class and accessibility fallback/reduction behavior.

## Rules

1. Spawn VFX only after/while the authoritative logical state says the event exists; particles/screenshake never create hits or damage.

2. Lifetime, opacity, shake and particle counts are authored project values, not universal millisecond constants.

3. Reduced-flash/motion settings preserve required information through pose/UI/audio/other supported channels rather than silently changing gameplay.

4. Camera offsets route through the camera safety/collision contract (`camera-anti-clip`) when they change the final camera transform.

5. Performance degradation removes/scales optional presentation according to `performance-budget`; it never removes gameplay collision/data.

6. Cancellation, rollback/re-simulation, retry and scene teardown use stable event/effect identity to avoid duplicate or stale effects.

+ 7. Entity-bound effects (projectile bodies, beams, auras, weapon glows) end on every authoritative removal path: impact, block, mutual cancel, expiry, owner reset and scene/round teardown. As a fallback, each presentation update reconciles live effect IDs against the authoritative entity set and retires orphans. Orphans are logged, because each one means an end event is missing.

+ 8. Full-screen accents in the same beat (flash, impact/negative frame, focus or speed lines, vignette) declare a sequence or priority so one does not mask another. They render beneath HUD-critical state unless the project explicitly allows covering it.

+ 9. Size, anchor and direction come from event and actor data: contact point, actor scale and attacker-to-defender direction. Review them in frame captures for occlusion of critical reads such as the defender's face/pose or the HUD.

+ 10. Trails and smears sample skeletal sockets after the current pose update and end with the action instance's authored window. Reduced settings remove them without removing required information.

## Accept

Replay identical logical traces with VFX on/off/reduced and under re-simulation/retry where relevant. Gameplay state is identical; effect instances have explainable event IDs, cleanup and fallback behavior.

+ Review composition from captures taken at fixed offsets after a named event. Freeze-on-event debug hooks are acceptable evidence when labeled as such. A reduced run shows zero instances of the reduced optional classes. A mutual-cancel or expiry trace leaves no live entity-bound effect.