diff --git a/src/AcDream.Core.Net/WorldSession.cs b/src/AcDream.Core.Net/WorldSession.cs
index 3389fb7..5c2bf20 100644
--- a/src/AcDream.Core.Net/WorldSession.cs
+++ b/src/AcDream.Core.Net/WorldSession.cs
@@ -1,6 +1,7 @@
 using System.Buffers.Binary;
 using System.Net;
 using System.Threading.Channels;
+using AcDream.Core.Combat;
 using AcDream.Core.Net.Cryptography;
 using AcDream.Core.Net.Messages;
 using AcDream.Core.Net.Packets;
@@ -909,6 +910,48 @@ public sealed class WorldSession : IDisposable
         SendGameAction(body);
     }
 
+    /// <summary>Send retail ChangeCombatMode (0x0053).</summary>
+    public void SendChangeCombatMode(CombatMode mode)
+    {
+        uint seq = NextGameActionSequence();
+        byte[] body = CharacterActions.BuildChangeCombatMode(
+            seq,
+            (CharacterActions.CombatMode)(uint)mode);
+        SendGameAction(body);
+    }
+
+    /// <summary>Send retail TargetedMeleeAttack (0x0008).</summary>
+    public void SendMeleeAttack(uint targetGuid, AttackHeight attackHeight, float powerLevel)
+    {
+        uint seq = NextGameActionSequence();
+        byte[] body = AttackTargetRequest.BuildMelee(
+            seq,
+            targetGuid,
+            (uint)attackHeight,
+            powerLevel);
+        SendGameAction(body);
+    }
+
+    /// <summary>Send retail TargetedMissileAttack (0x000A).</summary>
+    public void SendMissileAttack(uint targetGuid, AttackHeight attackHeight, float accuracyLevel)
+    {
+        uint seq = NextGameActionSequence();
+        byte[] body = AttackTargetRequest.BuildMissile(
+            seq,
+            targetGuid,
+            (uint)attackHeight,
+            accuracyLevel);
+        SendGameAction(body);
+    }
+
+    /// <summary>Send retail CancelAttack (0x01B7).</summary>
+    public void SendCancelAttack()
+    {
+        uint seq = NextGameActionSequence();
+        byte[] body = AttackTargetRequest.BuildCancel(seq);
+        SendGameAction(body);
+    }
+
     /// <summary>
     /// Phase I.6: send a TurbineChat <c>RequestSendToRoomById</c> to a
     /// global community room (General / Trade / LFG / Roleplay /
diff --git a/src/AcDream.Core/Combat/CombatModel.cs b/src/AcDream.Core/Combat/CombatModel.cs
index a70d6d7..693fe52 100644
--- a/src/AcDream.Core/Combat/CombatModel.cs
+++ b/src/AcDream.Core/Combat/CombatModel.cs
@@ -7,14 +7,17 @@ namespace AcDream.Core.Combat;
 // Full research: docs/research/deepdives/r02-combat-system.md
 // ─────────────────────────────────────────────────────────────────────
 
+[Flags]
 public enum CombatMode
 {
     Undef     = 0,
-    NonCombat = 1,
-    Melee     = 2,
-    Missile   = 3,
-    Magic     = 4,
-    Peaceful  = 5,
+    NonCombat = 0x01,
+    Melee     = 0x02,
+    Missile   = 0x04,
+    Magic     = 0x08,
+
+    ValidCombat  = NonCombat | Melee | Missile | Magic,
+    CombatCombat = Melee | Missile | Magic,
 }
 
 public enum AttackHeight
diff --git a/src/AcDream.Core/Combat/CombatState.cs b/src/AcDream.Core/Combat/CombatState.cs
index 7f6772a..15018b0 100644
--- a/src/AcDream.Core/Combat/CombatState.cs
+++ b/src/AcDream.Core/Combat/CombatState.cs
@@ -39,6 +39,8 @@ public sealed class CombatState
 {
     private readonly ConcurrentDictionary<uint, float> _healthByGuid = new();
 
+    public CombatMode CurrentMode { get; private set; } = CombatMode.NonCombat;
+
     /// <summary>Fires when a target's health percent changes (from UpdateHealth).</summary>
     public event Action<uint /*guid*/, float /*percent*/>? HealthChanged;
 
@@ -60,6 +62,9 @@ public sealed class CombatState
     /// <summary>The server accepted the attack and the power bar/animation can begin.</summary>
     public event Action? AttackCommenced;
 
+    /// <summary>The locally requested or server-confirmed combat mode changed.</summary>
+    public event Action<CombatMode>? CombatModeChanged;
+
     /// <summary>
     /// Fires when the server confirms the player landed a killing blow
     /// (GameEvent <c>KillerNotification (0x01AD)</c>). Event payload is
@@ -97,6 +102,15 @@ public sealed class CombatState
         HealthChanged?.Invoke(targetGuid, healthPercent);
     }
 
+    public void SetCombatMode(CombatMode mode)
+    {
+        if (CurrentMode == mode)
+            return;
+
+        CurrentMode = mode;
+        CombatModeChanged?.Invoke(mode);
+    }
+
     public void OnVictimNotification(
         string attackerName, uint attackerGuid, uint damageType, uint damage,
         uint hitQuadrant, uint critical, uint attackType)
diff --git a/tests/AcDream.Core.Net.Tests/WorldSessionCombatTests.cs b/tests/AcDream.Core.Net.Tests/WorldSessionCombatTests.cs
new file mode 100644
index 0000000..0bdd0be
--- /dev/null
+++ b/tests/AcDream.Core.Net.Tests/WorldSessionCombatTests.cs
@@ -0,0 +1,77 @@
+using System.Net;
+using AcDream.Core.Combat;
+using AcDream.Core.Net;
+using AcDream.Core.Net.Messages;
+
+namespace AcDream.Core.Net.Tests;
+
+public sealed class WorldSessionCombatTests
+{
+    private static WorldSession NewSession()
+    {
+        var ep = new IPEndPoint(IPAddress.Loopback, 65000);
+        return new WorldSession(ep);
+    }
+
+    [Fact]
+    public void SendChangeCombatMode_UsesSequenceAndRetailModeValue()
+    {
+        using var session = NewSession();
+        byte[]? captured = null;
+        session.GameActionCapture = body => captured = body;
+
+        session.SendChangeCombatMode(CombatMode.Magic);
+
+        Assert.NotNull(captured);
+        Assert.Equal(CharacterActions.BuildChangeCombatMode(
+            1,
+            CharacterActions.CombatMode.Magic), captured);
+    }
+
+    [Fact]
+    public void SendMeleeAttack_UsesRetailMeleeBuilder()
+    {
+        using var session = NewSession();
+        byte[]? captured = null;
+        session.GameActionCapture = body => captured = body;
+
+        session.SendMeleeAttack(0x50000002u, AttackHeight.High, 0.75f);
+
+        Assert.NotNull(captured);
+        Assert.Equal(AttackTargetRequest.BuildMelee(
+            1,
+            0x50000002u,
+            (uint)AttackHeight.High,
+            0.75f), captured);
+    }
+
+    [Fact]
+    public void SendMissileAttack_UsesRetailMissileBuilder()
+    {
+        using var session = NewSession();
+        byte[]? captured = null;
+        session.GameActionCapture = body => captured = body;
+
+        session.SendMissileAttack(0x50000003u, AttackHeight.Low, 0.5f);
+
+        Assert.NotNull(captured);
+        Assert.Equal(AttackTargetRequest.BuildMissile(
+            1,
+            0x50000003u,
+            (uint)AttackHeight.Low,
+            0.5f), captured);
+    }
+
+    [Fact]
+    public void SendCancelAttack_UsesRetailCancelBuilder()
+    {
+        using var session = NewSession();
+        byte[]? captured = null;
+        session.GameActionCapture = body => captured = body;
+
+        session.SendCancelAttack();
+
+        Assert.NotNull(captured);
+        Assert.Equal(AttackTargetRequest.BuildCancel(1), captured);
+    }
+}
diff --git a/tests/AcDream.Core.Tests/Combat/CombatStateTests.cs b/tests/AcDream.Core.Tests/Combat/CombatStateTests.cs
index d9baae8..d55f4ee 100644
--- a/tests/AcDream.Core.Tests/Combat/CombatStateTests.cs
+++ b/tests/AcDream.Core.Tests/Combat/CombatStateTests.cs
@@ -27,6 +27,40 @@ public sealed class CombatStateTests
         Assert.Equal(1f, state.GetHealthPercent(0xDEAD));
     }
 
+    [Fact]
+    public void CombatMode_UsesRetailAceBitValues()
+    {
+        Assert.Equal(1, (int)CombatMode.NonCombat);
+        Assert.Equal(2, (int)CombatMode.Melee);
+        Assert.Equal(4, (int)CombatMode.Missile);
+        Assert.Equal(8, (int)CombatMode.Magic);
+    }
+
+    [Fact]
+    public void SetCombatMode_TracksCurrentMode_AndFiresEvent()
+    {
+        var state = new CombatState();
+        CombatMode? seen = null;
+        state.CombatModeChanged += mode => seen = mode;
+
+        state.SetCombatMode(CombatMode.Missile);
+
+        Assert.Equal(CombatMode.Missile, state.CurrentMode);
+        Assert.Equal(CombatMode.Missile, seen);
+    }
+
+    [Fact]
+    public void OnCombatCommenceAttack_FiresAttackCommenced()
+    {
+        var state = new CombatState();
+        bool seen = false;
+        state.AttackCommenced += () => seen = true;
+
+        state.OnCombatCommenceAttack();
+
+        Assert.True(seen);
+    }
+
     [Fact]
     public void OnVictimNotification_FiresDamageTaken()
     {