diff --git a/src/AcDream.Plugins.MossTank/MossTankCommands.cs b/src/AcDream.Plugins.MossTank/MossTankCommands.cs
index cfda5ca95..b8e9fc643 100644
--- a/src/AcDream.Plugins.MossTank/MossTankCommands.cs
+++ b/src/AcDream.Plugins.MossTank/MossTankCommands.cs
@@ -425,17 +425,28 @@ internal sealed partial class MossTankPanel
                     WriteVtank("Option set: Invalid option specified.");
                     return;
                 }
-                if (rawValue.Length == 0 || !TryParseOptionValue(rawValue, out ExpressionValue value))
+                canonical = VtankOptionCatalog.Canonical(name);
+                VtankSettingValueType declaredType = VtankOptionCatalog.DeclaredType(canonical);
+                if (rawValue.Length == 0 || !TryParseOptionValue(rawValue, declaredType, out ExpressionValue value))
                 {
-                    WriteVtank("Option set: Invalid value specified.");
+                    // Round 3 item 6: retail's exact failure text
+                    // (refs/vtank/decompiled/uTank2/PluginCore.cs:5501,5508,5612)
+                    // names the option and the CLR type its Settings row
+                    // actually declares (gy's own m_a, ToString()'d).
+                    WriteVtank(
+                        "Option set: Invalid value specified. Proper type of "
+                        + canonical + " is " + DeclaredClrTypeName(declaredType) + ".");
                     return;
                 }
-                canonical = VtankOptionCatalog.Canonical(name);
                 SetMetaOption(canonical, value);
                 if (operation.Equals("setinall", StringComparison.OrdinalIgnoreCase))
                 {
+                    // Round 3 item 6: retail's exact bk.a text
+                    // (refs/vtank/decompiled/bk.cs:32) — no "= value" suffix,
+                    // and the count is every .usd file scanned, not just the
+                    // ones that already had a row for this name.
                     int count = _profiles.SetOptionInAll(canonical, _allSettings);
-                    WriteVtank($"Set option {canonical} in {count} profile(s) = {GetMetaOption(canonical).ToDisplayString()}");
+                    WriteVtank($"Done saving setting {canonical} to all profiles. (Changed {count} profiles)");
                 }
                 else
                 {
@@ -965,22 +976,107 @@ internal sealed partial class MossTankPanel
         return result;
     }
 
-    private static bool TryParseOptionValue(string source, out ExpressionValue value)
+    /// <summary>
+    /// Free-form parse (no catalog type to check against) for callers like
+    /// the Advanced Options editor, which can target names outside the 137-
+    /// row catalog: best-effort bool, then number, then string.
+    /// </summary>
+    private static bool TryParseOptionValue(string source, out ExpressionValue value) =>
+        TryParseOptionValue(source, declaredType: null, out value);
+
+    /// <summary>
+    /// Round 3 item 6: <c>/vt opt set</c>/<c>setinall</c> validate the typed
+    /// value against the catalog's OWN declared <see cref="VtankSettingValueType"/>
+    /// (retail's <c>eSettingValueType</c>) rather than accepting anything —
+    /// a value that does not parse as that type fails with retail's exact
+    /// "Proper type of X is Y." text (<see cref="HandleOptionCommand"/>).
+    /// <paramref name="declaredType"/> is <see langword="null"/> only for
+    /// the free-form Advanced Options editor, which keeps the original lax
+    /// best-effort behavior.
+    /// </summary>
+    private static bool TryParseOptionValue(
+        string source,
+        VtankSettingValueType? declaredType,
+        out ExpressionValue value)
     {
-        if (bool.TryParse(source, out bool boolean))
+        if (source.Length == 0)
         {
-            value = ExpressionValue.Boolean(boolean);
-            return true;
+            value = default;
+            return false;
         }
-        if (double.TryParse(source, NumberStyles.Float, CultureInfo.InvariantCulture, out double number))
+        switch (declaredType)
         {
-            value = ExpressionValue.Number(number);
-            return true;
+            case VtankSettingValueType.Bool:
+                if (bool.TryParse(source, out bool boolean))
+                {
+                    value = ExpressionValue.Boolean(boolean);
+                    return true;
+                }
+                value = default;
+                return false;
+            case VtankSettingValueType.Int:
+            case VtankSettingValueType.Enum:
+                if (int.TryParse(
+                    source, NumberStyles.Integer, CultureInfo.InvariantCulture, out int integer))
+                {
+                    value = ExpressionValue.Number(integer);
+                    return true;
+                }
+                value = default;
+                return false;
+            case VtankSettingValueType.Double:
+            case VtankSettingValueType.Single:
+                if (double.TryParse(
+                    source, NumberStyles.Float, CultureInfo.InvariantCulture, out double number))
+                {
+                    value = ExpressionValue.Number(number);
+                    return true;
+                }
+                value = default;
+                return false;
+            case VtankSettingValueType.String:
+                value = ExpressionValue.String(source);
+                return true;
+            default:
+                // No declared type (free-form editor) or VtankSettingValueType.Custom
+                // (the one non-scalar row, RechargeHandlerSet, never reached
+                // through /vt opt set): keep the original lax parse.
+                if (bool.TryParse(source, out bool freeBoolean))
+                {
+                    value = ExpressionValue.Boolean(freeBoolean);
+                    return true;
+                }
+                if (double.TryParse(
+                    source, NumberStyles.Float, CultureInfo.InvariantCulture, out double freeNumber))
+                {
+                    value = ExpressionValue.Number(freeNumber);
+                    return true;
+                }
+                value = ExpressionValue.String(source);
+                return true;
         }
-        value = ExpressionValue.String(source);
-        return source.Length != 0;
     }
 
+    /// <summary>
+    /// The CLR type name retail's exact failure text names
+    /// (<c>refs/vtank/decompiled/uTank2/PluginCore.cs:5501,5508,5612</c>:
+    /// <c>cw2[1].b().ToString()</c> — the Settings row's underlying
+    /// <c>gy</c> cell type, <see cref="Type.ToString"/>'d). Retail stores an
+    /// Enum-declared row as a plain int cell (confirmed against the
+    /// UseArcs row in the shipped defaultsettings.usd fixture), so it also
+    /// reads "System.Int32".
+    /// </summary>
+    private static string DeclaredClrTypeName(VtankSettingValueType type) => type switch
+    {
+        VtankSettingValueType.Bool => "System.Boolean",
+        VtankSettingValueType.Double => "System.Double",
+        VtankSettingValueType.Int => "System.Int32",
+        VtankSettingValueType.Single => "System.Single",
+        VtankSettingValueType.String => "System.String",
+        VtankSettingValueType.Enum => "System.Int32",
+        _ => "System.Object",
+    };
+
     private bool TryParseCoordinates(string source, out PluginNavigationPosition position)
     {
         position = default;
diff --git a/src/AcDream.Plugins.MossTank/MossTankProfileStore.cs b/src/AcDream.Plugins.MossTank/MossTankProfileStore.cs
index 29fd46fb4..769b2a8b3 100644
--- a/src/AcDream.Plugins.MossTank/MossTankProfileStore.cs
+++ b/src/AcDream.Plugins.MossTank/MossTankProfileStore.cs
@@ -328,13 +328,22 @@ internal sealed class MossTankProfileStore
     }
 
     /// <summary>
-    /// VTank's <c>opt setinall</c>: patch every known <c>.usd</c> file's
-    /// Settings row for <paramref name="name"/> (including the currently
-    /// bound character's own file even if it has never been saved before),
-    /// leaving every other row and every other table untouched. The live
-    /// value has already been applied by the caller (<c>SetMetaOption</c>)
-    /// before this runs; this only persists that same value into every
-    /// profile file.
+    /// VTank's <c>opt setinall</c> (<c>bk.a</c>, <c>refs/vtank/decompiled/bk.cs:6-35</c>):
+    /// patch every known <c>.usd</c> file's Settings row for
+    /// <paramref name="name"/> (including the currently bound character's
+    /// own file even if it has never been saved before), leaving every
+    /// other row and every other table untouched. The live value has
+    /// already been applied by the caller (<c>SetMetaOption</c>) before
+    /// this runs; this only persists that same value into every profile
+    /// file. Round 3 item 6: when a file's Settings table has no row for
+    /// this name at all, <c>bk.a</c> APPENDS a new one
+    /// (<c>bk.cs:22-27</c>: <c>cw3[0]=name, cw3[1]=value</c>, every other
+    /// column left at its default-constructed <c>gy</c> — a "void" cell,
+    /// <c>gy.cs:98-101</c>) rather than skipping that file, and the caller
+    /// reports <c>files.Length</c> (every <c>.usd</c> file scanned,
+    /// regardless of whether that file's own row already existed) —
+    /// <see cref="SetOptionInAll"/> returns that same file count, not a
+    /// per-row "successfully changed" tally.
     /// </summary>
     public int SetOptionInAll(string name, VtankSettingsProfileSerializer.AllSettings current)
     {
@@ -370,7 +379,6 @@ internal sealed class MossTankProfileStore
                 ? DynamicSettingDocument.From(liveDynamicValue)
                 : null;
 
-        int updated = 0;
         foreach (string fileName in fileNames)
         {
             string? text = ReadUsdText(fileName);
@@ -395,7 +403,16 @@ internal sealed class MossTankProfileStore
                 candidate.Cells[nameColumn].AsString().Equals(
                     canonical, StringComparison.OrdinalIgnoreCase));
             if (row is null)
-                continue;
+            {
+                // bk.cs:22-27: append a brand-new row rather than skip this
+                // file. Every column other than [0]=name/[1]=value stays a
+                // void gy() cell (gy.cs:98-101 writes only "0" for one).
+                row = new VtankRow();
+                for (int column = 0; column < table.ColumnNames.Count; column++)
+                    row.Cells.Add(new VtankCell { Tag = "0" });
+                row.Cells[nameColumn] = VtankCell.String(canonical);
+                table.Rows.Add(row);
+            }
             row.Cells[valueColumn] = captured;
             WriteUsdText(fileName, database.Render());
             if (fileName.Equals(_currentDatabaseFileName, StringComparison.Ordinal))
@@ -407,9 +424,11 @@ internal sealed class MossTankProfileStore
                 sidecar.CombatDynamicSettings[canonical] = dynamicDocument;
                 WriteJson(SideCarKey(fileName), sidecar);
             }
-            updated++;
         }
-        return updated;
+        // bk.cs:32: PluginCore.a(... + files.Length + " profiles)") reports
+        // the TOTAL file count scanned, not a per-file "did it actually
+        // change" tally.
+        return fileNames.Count;
     }
 
     // ------------------------------------------------------------------
diff --git a/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs b/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs
index 64381a363..0d5bddc5d 100644
--- a/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs
+++ b/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs
@@ -1517,6 +1517,97 @@ public sealed class MossTankPanelTests
             "uboptget['AttackDistance']").AsNumber(), precision: 7);
     }
 
+    /// <summary>
+    /// Round 3 item 6: retail's bk.a text (refs/vtank/decompiled/bk.cs:32)
+    /// is "Done saving setting X to all profiles. (Changed N profiles)" —
+    /// no "= value" suffix, unlike the plain "set" success message.
+    /// </summary>
+    [Fact]
+    public void VtankSetInAllReportsRetailsExactMessageText()
+    {
+        var automation = new FakeAutomation();
+        var panel = new MossTankPanel(new FakeHost(automation));
+
+        Command(panel, "opt setinall AttackDistance 0.03");
+
+        string message = Assert.Single(automation.Messages, static text =>
+            text.StartsWith("Done saving setting", StringComparison.Ordinal));
+        Assert.StartsWith(
+            "Done saving setting AttackDistance to all profiles. (Changed ",
+            message,
+            StringComparison.Ordinal);
+        Assert.EndsWith(" profiles)", message, StringComparison.Ordinal);
+        Assert.DoesNotContain("=", message, StringComparison.Ordinal);
+    }
+
+    /// <summary>
+    /// Round 3 item 6: a value that does not parse as the catalog's own
+    /// declared type (EnableLooting is Bool) fails with retail's exact
+    /// text (refs/vtank/decompiled/uTank2/PluginCore.cs:5501,5508,5612).
+    /// </summary>
+    [Theory]
+    [InlineData("set")]
+    [InlineData("setinall")]
+    public void VtankOptSetRejectsAWrongTypedValueWithRetailsExactText(string operation)
+    {
+        var automation = new FakeAutomation();
+        var panel = new MossTankPanel(new FakeHost(automation));
+
+        Command(panel, $"opt {operation} EnableLooting notaboolean");
+
+        Assert.Equal(
+            "Option set: Invalid value specified. Proper type of EnableLooting is System.Boolean.",
+            Assert.Single(automation.Messages));
+    }
+
+    /// <summary>
+    /// Round 3 item 6: <c>bk.a</c> (refs/vtank/decompiled/bk.cs:22-27)
+    /// APPENDS a new Settings row — [0]=name, [1]=value, every other column
+    /// left as a void <c>gy()</c> cell — when a <c>.usd</c> file's Settings
+    /// table has no row for the option at all, rather than skipping that
+    /// file outright.
+    /// </summary>
+    [Fact]
+    public void SetOptionInAllAppendsARowWhenAFileHasNoneForThatSetting()
+    {
+        var storage = new MemoryStorage();
+        var automation = new FakeAutomation { Name = "Barris" };
+        // A hand-trimmed Settings table (4 real columns: Setting, Value,
+        // Description, SettingType) with exactly one row, for a DIFFERENT
+        // setting — "EnableLooting" is deliberately absent.
+        const string minimalUsd =
+            "1\r\nSettings\r\n4\r\nSetting\r\nValue\r\nDescription\r\nSettingType\r\n"
+            + "y\r\nn\r\nn\r\nn\r\n1\r\ns\r\nEnableNav\r\nb\r\nFalse\r\ns\r\n\r\ni\r\n1\r\n";
+        storage.Text["Other.usd"] = minimalUsd;
+
+        var store = new MossTankProfileStore(new FakeHost(automation, storage));
+        var settings = new VtankSettingsProfileSerializer.AllSettings
+        {
+            Combat = new CombatSettings(),
+            Buffs = new BuffSettings(),
+            Vitals = new VitalSettings(),
+            Inventory = new InventorySettings(),
+            Navigation = new NavigationSettings(),
+        };
+        settings.Inventory.Loot.Enabled = true;
+
+        int count = store.SetOptionInAll("EnableLooting", settings);
+
+        VtankDatabase rewritten = VtankDatabase.Parse(storage.Text["Other.usd"]);
+        VtankTable table = rewritten.Find("Settings")!;
+        int nameColumn = table.ColumnIndex("Setting");
+        int valueColumn = table.ColumnIndex("Value");
+        VtankRow appended = Assert.Single(table.Rows, row =>
+            row.Cells[nameColumn].AsString().Equals(
+                "EnableLooting", StringComparison.OrdinalIgnoreCase));
+        Assert.True(appended.Cells[valueColumn].AsBool());
+        // The remaining columns (Description/SettingType) stay void, never
+        // copied from the existing EnableNav row.
+        Assert.Equal("0", appended.Cells[2].Tag);
+        Assert.Equal("0", appended.Cells[3].Tag);
+        Assert.True(count >= 1);
+    }
+
     [Fact]
     public void VtankHelpAndExpressionsUseTheLocalCommandSurface()
     {