diff --git a/src/AcDream.Plugins.MossTank/MossTankPanel.cs b/src/AcDream.Plugins.MossTank/MossTankPanel.cs
index 57106108..f6b20534 100644
--- a/src/AcDream.Plugins.MossTank/MossTankPanel.cs
+++ b/src/AcDream.Plugins.MossTank/MossTankPanel.cs
@@ -189,6 +189,14 @@ internal sealed partial class MossTankPanel
         MonsterDamageType.None,
     ];
     private IReadOnlyList<string> _itemRows = Array.Empty<string>();
+    // Fix round C item F12: the same SortedCombatItemNames() pass that
+    // builds _itemRows (with the "   [no buffs]" suffix appended where it
+    // applies) also stores the raw, undecorated names here — the ONE
+    // place that decoration is added. ItemHandsColumn used to re-derive
+    // the base name by stripping the suffix back off each display row
+    // (BaseItemName), a second, opposite-direction definition of the same
+    // fact that could drift from the first if the suffix ever changed.
+    private IReadOnlyList<string> _itemBaseNames = Array.Empty<string>();
     private IReadOnlyList<string> _consumableRows = Array.Empty<string>();
     private int _selectedItemRow;
     private int _selectedConsumableRow;
@@ -203,6 +211,14 @@ internal sealed partial class MossTankPanel
     // adaptation" note) rather than inventing new profile-wide behavior.
     private readonly Dictionary<string, int> _itemHandedness =
         new(StringComparer.Ordinal);
+    // Fix round C item F7: ItemHandsColumn used to run a fresh
+    // .Select(...).ToArray() over _itemRows, PLUS a per-row BaseItemName
+    // suffix-strip, on every single retained-UI draw. Materialized once
+    // in RefreshItemEditors, refreshed by every real mutator that can
+    // change a row's handedness or the roster itself (see
+    // CycleItemHandsAtCore, DeleteItemRowAtCore, and every other
+    // RefreshItemEditors call site).
+    private IReadOnlyList<string> _itemHandsColumn = Array.Empty<string>();
     private static readonly string[] HandednessCycle =
         ["Auto", "1-Handed", "2-Handed"];
     private IReadOnlyList<string> _excludedComponentRows = Array.Empty<string>();
@@ -688,9 +704,7 @@ internal sealed partial class MossTankPanel
     // §1 "Tab: Items"; PluginCore.cs:8529-8562 — col 0 click deletes, col 1
     // click cycles handedness) ──────────────────────────────────────────
     public IReadOnlyList<string> ItemNameColumn => _itemRows;
-    public IReadOnlyList<string> ItemHandsColumn => _itemRows
-        .Select(row => HandednessCycle[HandednessIndex(BaseItemName(row))])
-        .ToArray();
+    public IReadOnlyList<string> ItemHandsColumn => _itemHandsColumn;
     public Action<int> DeleteItemRowAt => DeleteItemRowAtCore;
     public Action<int> CycleItemHandsAt => CycleItemHandsAtCore;
 
@@ -1799,11 +1813,16 @@ internal sealed partial class MossTankPanel
     private void RefreshItemEditors()
     {
         RefreshConsumableCategories();
-        _itemRows = SortedCombatItemNames()
+        string[] baseNames = SortedCombatItemNames();
+        _itemBaseNames = baseNames;
+        _itemRows = baseNames
             .Select(name => _noBuffItemNames.Contains(name)
                 ? name + "   [no buffs]"
                 : name)
             .ToArray();
+        _itemHandsColumn = baseNames
+            .Select(name => HandednessCycle[HandednessIndex(name)])
+            .ToArray();
         _consumableRows = _combatSettings.ConsumableNames
             .OrderBy(static name => name, StringComparer.Ordinal)
             .ToArray();
@@ -1822,14 +1841,6 @@ internal sealed partial class MossTankPanel
             _excludedComponentRows.Count);
     }
 
-    private static string BaseItemName(string displayRow)
-    {
-        const string suffix = "   [no buffs]";
-        return displayRow.EndsWith(suffix, StringComparison.Ordinal)
-            ? displayRow[..^suffix.Length]
-            : displayRow;
-    }
-
     private int HandednessIndex(string name) =>
         _itemHandedness.TryGetValue(name, out int value) ? value : 0;
 
@@ -1849,11 +1860,15 @@ internal sealed partial class MossTankPanel
 
     private void CycleItemHandsAtCore(int row)
     {
-        string[] names = SortedCombatItemNames();
-        if ((uint)row >= (uint)names.Length)
+        if ((uint)row >= (uint)_itemBaseNames.Count)
             return;
-        string name = names[row];
+        string name = _itemBaseNames[row];
         _itemHandedness[name] = (HandednessIndex(name) + 1) % HandednessCycle.Length;
+        // Fix round C item F7: ItemHandsColumn is now materialized in
+        // RefreshItemEditors, not recomputed on every read — this real
+        // mutator (the grid's own "click cycles handedness" action) must
+        // refresh it so the next read reflects the new cycle position.
+        RefreshItemEditors();
     }
 
     private const string ExcludedComponentDelimiter = "; ";
diff --git a/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs b/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs
index 1327f616..4a6e4874 100644
--- a/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs
+++ b/tests/AcDream.Plugins.MossTank.Tests/MossTankPanelTests.cs
@@ -943,6 +943,39 @@ public sealed class MossTankPanelTests
         Assert.Equal(["Ice Wand"], panel.ItemNameColumn);
     }
 
+    [Fact]
+    public void ItemHandsColumnDoesNotReallocateOnEveryReadAndNoBuffSuffixNeverLeaks()
+    {
+        // Fix round C item F7: ItemHandsColumn used to run a fresh
+        // .Select(...).ToArray() over _itemRows PLUS a per-row BaseItemName
+        // suffix-strip on every single retained-UI draw. It is now
+        // materialized once in RefreshItemEditors: repeated reads with no
+        // mutation in between must return the SAME array instance.
+        // Fix round C item F12: the handedness lookup now uses the raw
+        // base-name array captured alongside the decorated display row
+        // (ONE place the "   [no buffs]" suffix is added, in
+        // RefreshItemEditors) instead of parsing the suffix back off — an
+        // item added with noBuffs must still resolve its own handedness
+        // correctly, proving the fold didn't break the no-buffs case.
+        var automation = new FakeAutomation
+        {
+            ItemEntries = [Item(10, "Fire Sword", 1)],
+        };
+        var host = new FakeHost(automation);
+        var panel = new MossTankPanel(host);
+        host.Selection.Select(10);
+        panel.AddSelectedItemNoBuffs();
+        Assert.Equal(["Fire Sword   [no buffs]"], panel.ItemNameColumn);
+
+        Assert.Same(panel.ItemHandsColumn, panel.ItemHandsColumn);
+        Assert.Equal("Auto", panel.ItemHandsColumn[0]);
+
+        panel.CycleItemHandsAt(0);
+        IReadOnlyList<string> afterCycle = panel.ItemHandsColumn;
+        Assert.Equal("1-Handed", afterCycle[0]);
+        Assert.Same(afterCycle, panel.ItemHandsColumn);
+    }
+
     [Fact]
     public void ConsumablesLeftListRowClickRemovesTheRowDirectly()
     {