Combat

Status Effects

Timed opaque markers (buffs/debuffs) applied to entities.

Server: services.AddCrossplayStatusEffects();
Unity package: com.crossplay.statuseffects
Depends on: world

Seams you implement 1

Crossplay calls these; your game supplies them. Each ships an inert or permissive default, so register yours before services.AddCrossplayStatusEffects(); and it wins.

IStatusEffectRules game SPI

SPI the game implements to give effects their meaning — a burning DoT modifies a stat on tick, a stun gates ability rules, a shield changes damage math. Default: pure timed markers. Register your own BEFORE AddCrossplayStatusEffects (a TryAdd seam). All callbacks fire on the poll thread; the framework already handles the timers and replication — the rules only apply CONSEQUENCE.

sealed class EffectRules : IStatusEffectRules
{
    public void OnApplied(long id, ushort effectId, byte[] data) { }
    public void OnTick(long id, ushort effectId, byte[] data, float seconds)
    {
        if (effectId == Burning) _stats.Modify(id, HealthStatId, -5 * seconds); // DoT
    }
    public void OnExpired(long id, ushort effectId) { }
}
// services.AddSingleton<IStatusEffectRules, EffectRules>(); // BEFORE AddCrossplayStatusEffects()

void OnApplied(long entityId, ushort effectId, byte[] data)
An effect landed (fresh or refreshed) — data is the opaque payload it was applied with.
void OnExpired(long entityId, ushort effectId)
The effect ended (expired on its timer or removed early) — undo any lingering consequence.
void OnTick(long entityId, ushort effectId, byte[] data, float intervalSeconds)
The periodic tick, once per intervalSeconds per live effect (apply DoT/aura math here).

Services you call 1

Crossplay implements these. Resolve them from DI and call them from your own systems.

IStatusEffectService

Server-side API for applying timed effects to world entities — the game calls this from its own logic (an ability that stuns, a trap that poisons); the framework runs the timers, replication, and expiry.

bool Apply(long entityId, ushort effectId, float durationSeconds, byte[] data = null)
Applies (or refreshes — same id replaces) an effect for a duration. False when the duration is ≤ 0, the entity is unknown, or the per-entity effect cap is reached.
bool Has(long entityId, ushort effectId)
True while the entity carries the effect (rules use this to gate: stunned?).
bool Remove(long entityId, ushort effectId)
Removes an effect early. False when not present.

Configuration 1

Every tunable lives in an options object — there are no magic numbers to hunt for.

StatusEffectOptions

Configurable status-effect parameters (defaults here; never inlined in logic).

int MaxEffectsPerEntity { get; set; }
Most simultaneous effects per entity.
float TickIntervalSeconds { get; set; }
Seconds between periodic-tick callbacks into the rules (DoTs, auras…).

Wire messages 1

The protocol this piece speaks. Ids are allocated per piece so they can never collide.

2501 EntityEffects

Server → observers (and the owner): the entity's full current effect list — sent on any change and replayed on interest reveal, so late arrivals render the right state.

Unity services you inject 1

Crossplay binds these in the client context. Inject and call them from your own MonoBehaviours and presenters.

IStatusEffectsClient

The StatusEffects piece, client side: every visible entity's current timed effects (opaque, game-defined), pushed on change and replayed on reveal — drive your own icons/particles/tints. Smoothing: RemainingOf counts each effect's timer DOWN locally between server pushes, so an on-screen duration ticks smoothly instead of jumping once a second. The next server push re-syncs it. Presentation only; the server owns expiry.

event Action<long, EffectInstance[]> EffectsChanged
An entity's effect list changed (the full current list).
EffectInstance[] EffectsOf(long entityId)
The latest known effect list for an entity (empty when none).
float RemainingOf(long entityId, ushort effectId)
An effect's remaining seconds, decremented locally since the last push (0 when absent).

UI views you can replace 1

Each ships a working uGUI panel you can drag into a scene. Substitute your own view to keep the logic and change the look — the presenter never knows.

ICrossplayStatusEffectsView

Narrow contract the presenter drives. UI-only: render calls in. The StatusEffects wire is pure server push (there is no client request path), so this view raises no intents.