diff --git a/src/AcDream.Core/Chat/WeenieErrorMessages.cs b/src/AcDream.Core/Chat/WeenieErrorMessages.cs
index bc1abb22..26a4bf00 100644
--- a/src/AcDream.Core/Chat/WeenieErrorMessages.cs
+++ b/src/AcDream.Core/Chat/WeenieErrorMessages.cs
@@ -254,6 +254,28 @@ public static class WeenieErrorMessages
         [0x413u] = new("%s is already one of your followers", RetailLogTextType.ClientLocal),
         [0x414u] = new("You are not in an allegiance!", RetailLogTextType.ClientLocal),
         [0x416u] = new("%s cannot have any more Vassals", RetailLogTextType.ClientLocal),
+        // Campaign FA slice FA1 (2026-08-11): 0x0417-0x041C
+        // (FellowshipIgnoringRequests/FellowshipSquelched/
+        // FellowshipMaxDistanceExceeded/FellowshipMember/
+        // FellowshipIllegalLevel/FellowshipRecruitBusy) are INTENTIONALLY
+        // absent — verified, not overlooked. Re-ran this table's own
+        // methodology (the class-doc's binary sweep) specifically for
+        // these six ids: `grep`-walked the ENTIRE 1.4M-line
+        // acclient_2013_pseudo_c.txt for every literal/case-label
+        // comparison against each of 0x417..0x41c and found ZERO hits
+        // anywhere in the file, then independently walked
+        // HandleFailureEvent's own ~3350-line case-label list
+        // (0x40a..0x489 switch block) and confirmed the sequence goes
+        // ...case 0x414: case 0x416: case 0x41d:... with NO case for
+        // 0x417-0x41c in between. Retail's Sept-2013 client has no
+        // display text for any of these six ids — they fall through to
+        // the "no case matched" outcome this table already models via
+        // Resolve()'s null-Text/no-display return. ACE never sends any of
+        // them (only 0x0417 and 0x04DB below are on a live ACE send path,
+        // and 0x0417 shows nothing in retail regardless). Do not add rows
+        // for these — that would be invented English with no retail
+        // anchor, exactly the class of mistake SHOULD-FIX 4 fixed for the
+        // table's no-default-case rule.
         [0x41Du] = new("You must be the leader of a Fellowship", RetailLogTextType.ClientLocal),
         [0x41Eu] = new("Your Fellowship is full", RetailLogTextType.ClientLocal),
         [0x41Fu] = new("That Fellowship name is not permitted", RetailLogTextType.ClientLocal),
@@ -376,6 +398,17 @@ public static class WeenieErrorMessages
         [0x4D8u] = new("You have succeeded in untraining your %s skill!", RetailLogTextType.Default),
         [0x4D9u] = new("Although you cannot untrain your %s skill, you have succeeded in recovering all the experience you had invested in it.", RetailLogTextType.Default),
         [0x4DAu] = new("You have too many credits invested in specialized skills already! Before you can specialize your %s skill, you will need to unspecialize some other skill.", RetailLogTextType.Default),
+        // Campaign FA slice FA1 (2026-08-11): 0x04DB (FellowshipDeclined)
+        // and 0x04DC (FellowshipTimeout) are INTENTIONALLY absent, same
+        // finding as the 0x0417-0x041C block above. The switch's case
+        // sequence in this address range goes
+        // ...case 0x4da: case 0x4dd:... — 0x4db/0x4dc have no case. This
+        // is the sharper of the two gaps: ACE actually sends
+        // FellowshipDeclined (Fellowship.cs:147, on a recruit refusal),
+        // so a live server event genuinely produces NO text in the
+        // Sept-2013 client — acdream's current silent-drop behavior for
+        // it is therefore retail-faithful, not a bug to fix by inventing
+        // a line retail never showed.
         [0x4DDu] = new("You have failed to alter your attributes.", RetailLogTextType.Default),
         [0x4DEu] = new("%s", RetailLogTextType.Default),
         [0x4DFu] = new("%s", RetailLogTextType.Default),
diff --git a/tests/AcDream.Core.Tests/Chat/WeenieErrorMessagesTests.cs b/tests/AcDream.Core.Tests/Chat/WeenieErrorMessagesTests.cs
index f24b98ca..95f772b3 100644
--- a/tests/AcDream.Core.Tests/Chat/WeenieErrorMessagesTests.cs
+++ b/tests/AcDream.Core.Tests/Chat/WeenieErrorMessagesTests.cs
@@ -365,4 +365,30 @@ public sealed class WeenieErrorMessagesTests
         Assert.Equal("A drudge fails to affect you because $s cannot affect anyone!", text);
         Assert.Equal(RetailLogTextType.Magic, type);
     }
+
+    // ── Campaign FA slice FA1 (2026-08-11): the 8 "missing" fellowship ids ──
+    //
+    // Same class of proof as Format_0x051D_ReturnsNull_NoRetailCaseExists
+    // above: independently re-ran this file's own binary-sweep methodology
+    // (a full-text grep of acclient_2013_pseudo_c.txt for every
+    // literal/case-label comparison against these 8 ids, plus a manual
+    // walk of HandleFailureEvent's own case-label sequence around each)
+    // and found NO case for any of them anywhere in the Sept-2013 client.
+    // These are intentionally absent from the table, not overlooked —
+    // adding invented text for them would itself be the SHOULD-FIX-4 class
+    // of bug this table exists to avoid.
+    [Theory]
+    [InlineData(0x0417u)] // FellowshipIgnoringRequests — ACE sends this live; retail still shows nothing
+    [InlineData(0x0418u)] // FellowshipSquelched — ACE never sends it
+    [InlineData(0x0419u)] // FellowshipMaxDistanceExceeded — ACE never sends it
+    [InlineData(0x041Au)] // FellowshipMember — ACE never sends it
+    [InlineData(0x041Bu)] // FellowshipIllegalLevel — ACE never sends it
+    [InlineData(0x041Cu)] // FellowshipRecruitBusy — ACE never sends it (busy is a plain chat line instead)
+    [InlineData(0x04DBu)] // FellowshipDeclined — ACE sends this live; retail still shows nothing
+    [InlineData(0x04DCu)] // FellowshipTimeout — ACE never sends it
+    public void Resolve_FellowshipIdsAbsentFromHandleFailureEvent_ReturnsNoText(uint code)
+    {
+        var (text, _) = WeenieErrorMessages.Resolve(code, param: null);
+        Assert.Null(text);
+    }
 }