diff --git a/src/CounterDrone.Core/Algorithms/GaussianPuffDispersion.cs b/src/CounterDrone.Core/Algorithms/GaussianPuffDispersion.cs
index 7bbb49b..1e3e554 100644
--- a/src/CounterDrone.Core/Algorithms/GaussianPuffDispersion.cs
+++ b/src/CounterDrone.Core/Algorithms/GaussianPuffDispersion.cs
@@ -26,6 +26,7 @@ namespace CounterDrone.Core.Algorithms
         public ParticleParams Particles { get; } = new();
         public bool IsDissipated { get; private set; }
         public int Phase => _inPhase3 ? 3 : (_elapsed < 0.01f ? 1 : 2);
+        public float Elapsed => _elapsed;
 
         public void Initialize(AmmunitionSpec ammo, CombatScene env, Vector3 releasePos, float releaseTime)
         {
diff --git a/src/CounterDrone.Core/Algorithms/ICloudDispersionModel.cs b/src/CounterDrone.Core/Algorithms/ICloudDispersionModel.cs
index 99b97c5..014307e 100644
--- a/src/CounterDrone.Core/Algorithms/ICloudDispersionModel.cs
+++ b/src/CounterDrone.Core/Algorithms/ICloudDispersionModel.cs
@@ -15,5 +15,7 @@ namespace CounterDrone.Core.Algorithms
         bool IsDissipated { get; }
         /// <summary>当前扩散阶段：1=爆轰膨胀, 2=湍流扩散, 3=高斯扩散</summary>
         int Phase { get; }
+        /// <summary>云团已存在时间（秒）</summary>
+        float Elapsed { get; }
     }
 }
diff --git a/src/CounterDrone.Core/Simulation/SimulationEngine.cs b/src/CounterDrone.Core/Simulation/SimulationEngine.cs
index ea56da5..9ea4baf 100644
--- a/src/CounterDrone.Core/Simulation/SimulationEngine.cs
+++ b/src/CounterDrone.Core/Simulation/SimulationEngine.cs
@@ -241,7 +241,7 @@ namespace CounterDrone.Core.Simulation
             foreach (var d in _drones)
                 list.Add(new EntitySnapshot { EntityId = d.Id, EntityType = Models.EntityType.Drone, PosX = d.PosX, PosY = d.PosY, PosZ = d.PosZ, StateData = JsonSerializer.Serialize(new { damageStage = (int)_damageModel.GetDamageStage(1 - d.Hp), hp = d.Hp }) });
             foreach (var c in _clouds)
-                list.Add(new EntitySnapshot { EntityId = c.Id, EntityType = Models.EntityType.Cloud, PosX = c.Dispersion.Center.X, PosY = c.Dispersion.Center.Y, PosZ = c.Dispersion.Center.Z, StateData = JsonSerializer.Serialize(new { radius = c.Dispersion.Radius, opacity = c.Dispersion.Particles.Opacity, phase = c.Dispersion.Phase }) });
+                list.Add(new EntitySnapshot { EntityId = c.Id, EntityType = Models.EntityType.Cloud, PosX = c.Dispersion.Center.X, PosY = c.Dispersion.Center.Y, PosZ = c.Dispersion.Center.Z, StateData = JsonSerializer.Serialize(new { radius = c.Dispersion.Radius, opacity = c.Dispersion.Particles.Opacity, phase = c.Dispersion.Phase, elapsed = c.Dispersion.Elapsed }) });
             return list;
         }
     }
diff --git a/test/unit/CounterDrone.Core.Tests/AlgorithmFactoryTests.cs b/test/unit/CounterDrone.Core.Tests/AlgorithmFactoryTests.cs
index 742e4d1..87abc62 100644
--- a/test/unit/CounterDrone.Core.Tests/AlgorithmFactoryTests.cs
+++ b/test/unit/CounterDrone.Core.Tests/AlgorithmFactoryTests.cs
@@ -37,6 +37,7 @@ namespace CounterDrone.Core.Tests
         public ParticleParams Particles => new();
         public bool IsDissipated => false;
         public int Phase => 2;
+        public float Elapsed => 10f;
 
         public void Initialize(CounterDrone.Core.Models.AmmunitionSpec ammo,
             CounterDrone.Core.Models.CombatScene env, Vector3 releasePos, float releaseTime)