diff --git a/tests/AcDream.Core.Tests/Conformance/Issue119TowerDumpTests.cs b/tests/AcDream.Core.Tests/Conformance/Issue119TowerDumpTests.cs
new file mode 100644
index 00000000..6f011285
--- /dev/null
+++ b/tests/AcDream.Core.Tests/Conformance/Issue119TowerDumpTests.cs
@@ -0,0 +1,184 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Numerics;
+using DatReaderWriter;
+using DatReaderWriter.Options;
+using Xunit;
+using Xunit.Abstractions;
+using DatEnvCell = DatReaderWriter.DBObjs.EnvCell;
+using DatEnvironment = DatReaderWriter.DBObjs.Environment;
+using DatLandBlockInfo = DatReaderWriter.DBObjs.LandBlockInfo;
+
+namespace AcDream.Core.Tests.Conformance;
+
+/// <summary>
+/// #119 diagnostic dump (2026-06-11): the user stood inside the "old tower"
+/// and logged out — the next login snap pinned it: cell 0xAAB30107,
+/// AAB3-local ≈ (107, 59, 112). Symptoms: stair parts INVISIBLE (visible in
+/// retail — axiom) + an extraneous water barrel "in the middle of it".
+/// This dump prints the dat truth for the tower's cell neighbourhood:
+/// per-cell environment/structure, position, SeenOutside, the stair
+/// signature (distinct flat-face heights + ramp polys — the Issue113 dump's
+/// discriminator), the portal topology, the VisibleCells list, and every
+/// static object (id + position) — the barrel candidate and the stair
+/// owners read directly off the output.
+/// </summary>
+public sealed class Issue119TowerDumpTests
+{
+    private readonly ITestOutputHelper _out;
+    public Issue119TowerDumpTests(ITestOutputHelper output) => _out = output;
+
+    private const uint Landblock = 0xAAB30000u;
+    private const uint EnvironmentFilePrefix = 0x0D000000u;
+    private static readonly Vector3 TowerSpot = new(107.4f, 59.0f, 112.0f); // AAB3-local, from the [snap]
+
+    [Fact]
+    public void DumpTowerCellNeighbourhood()
+    {
+        var datDir = ConformanceDats.ResolveDatDir();
+        if (datDir is null) { _out.WriteLine("dats unavailable — skipped"); return; }
+        using var dats = new DatCollection(datDir, DatAccessType.Read);
+
+        var lbi = dats.Get<DatLandBlockInfo>(Landblock | 0xFFFEu);
+        Assert.NotNull(lbi);
+        _out.WriteLine($"=== LandBlockInfo 0x{Landblock | 0xFFFEu:X8}: NumCells={lbi!.NumCells}, Buildings={lbi.Buildings?.Count ?? 0} ===");
+        if (lbi.Buildings is not null)
+            for (int b = 0; b < lbi.Buildings.Count; b++)
+            {
+                var bld = lbi.Buildings[b];
+                _out.WriteLine(FormattableString.Invariant(
+                    $"  building[{b}] model=0x{bld.ModelId:X8} origin=({bld.Frame.Origin.X:F1},{bld.Frame.Origin.Y:F1},{bld.Frame.Origin.Z:F1}) portals={bld.Portals?.Count ?? 0}"));
+                if (bld.Portals is not null)
+                    foreach (var bp in bld.Portals)
+                        _out.WriteLine(FormattableString.Invariant(
+                            $"    bldPortal otherCell=0x{bp.OtherCellId:X4} stabs=[{string.Join(",", (bp.StabList ?? new List<ushort>()).Select(s => $"0x{s:X4}"))}]"));
+            }
+
+    foreach (uint low in EnumerateCells(lbi.NumCells))
+        {
+            uint id = Landblock | low;
+            var dc = dats.Get<DatEnvCell>(id);
+            if (dc is null) continue;
+
+            var env = dats.Get<DatEnvironment>(EnvironmentFilePrefix | dc.EnvironmentId);
+            if (env is null || !env.Cells.TryGetValue(dc.CellStructure, out var cs) || cs is null)
+            { _out.WriteLine($"cell 0x{id:X8}: env 0x{dc.EnvironmentId:X} struct {dc.CellStructure} MISSING"); continue; }
+
+            var world =
+                Matrix4x4.CreateFromQuaternion(dc.Position.Orientation) *
+                Matrix4x4.CreateTranslation(dc.Position.Origin);
+
+            // bounds + distance to the user's spot
+            var min = new Vector3(float.MaxValue);
+            var max = new Vector3(float.MinValue);
+            foreach (var kvp in cs.VertexArray.Vertices)
+            {
+                var p = Vector3.Transform(new Vector3(kvp.Value.Origin.X, kvp.Value.Origin.Y, kvp.Value.Origin.Z), world);
+                min = Vector3.Min(min, p);
+                max = Vector3.Max(max, p);
+            }
+            var center = (min + max) * 0.5f;
+            float dist = Vector2.Distance(new Vector2(center.X, center.Y), new Vector2(TowerSpot.X, TowerSpot.Y));
+            bool near = dist < 18f;
+            if (!near) continue;   // only the tower neighbourhood
+
+            // stair signature (Issue113 discriminator)
+            var flatHeights = new HashSet<int>();
+            int rampPolys = 0;
+            foreach (var poly in cs.Polygons.Values)
+            {
+                if (poly.VertexIds.Count < 3) continue;
+                var pts = new List<Vector3>(poly.VertexIds.Count);
+                bool ok = true;
+                foreach (var vid in poly.VertexIds)
+                {
+                    if (!cs.VertexArray.Vertices.TryGetValue((ushort)vid, out var v)) { ok = false; break; }
+                    pts.Add(Vector3.Transform(new Vector3(v.Origin.X, v.Origin.Y, v.Origin.Z), world));
+                }
+                if (!ok) continue;
+                // Newell normal
+                var n = Vector3.Zero;
+                for (int i = 0; i < pts.Count; i++)
+                {
+                    var a = pts[i]; var b = pts[(i + 1) % pts.Count];
+                    n.X += (a.Y - b.Y) * (a.Z + b.Z);
+                    n.Y += (a.Z - b.Z) * (a.X + b.X);
+                    n.Z += (a.X - b.X) * (a.Y + b.Y);
+                }
+                if (n.LengthSquared() < 1e-12f) continue;
+                n = Vector3.Normalize(n);
+                if (MathF.Abs(n.Z) > 0.9f)
+                    flatHeights.Add((int)MathF.Round(pts.Average(p => p.Z) * 4f)); // 25 cm bins
+                else if (MathF.Abs(n.Z) > 0.25f)
+                    rampPolys++;
+            }
+
+            bool seenOutside = dc.Flags.HasFlag(DatReaderWriter.Enums.EnvCellFlags.SeenOutside);
+            _out.WriteLine(FormattableString.Invariant(
+                $"cell 0x{id:X8} env=0x{dc.EnvironmentId:X4}/{dc.CellStructure} pos=({dc.Position.Origin.X:F1},{dc.Position.Origin.Y:F1},{dc.Position.Origin.Z:F1}) aabb=z[{min.Z:F1}..{max.Z:F1}] distXY={dist:F1} seenOutside={seenOutside} flatLevels={flatHeights.Count} rampPolys={rampPolys} polys={cs.Polygons.Count}"));
+
+            _out.WriteLine($"  portals: [{string.Join(" ", dc.CellPortals.Select(p => $"->0x{p.OtherCellId:X4}(poly{p.PolygonId},flags={(ushort)p.Flags})"))}]");
+            if (dc.VisibleCells is not null && dc.VisibleCells.Count > 0)
+                _out.WriteLine($"  visibleCells: [{string.Join(",", dc.VisibleCells.Select(v => $"0x{v:X4}"))}]");
+
+            if (dc.StaticObjects is not null)
+                foreach (var so in dc.StaticObjects)
+                    _out.WriteLine(FormattableString.Invariant(
+                        $"  static gfx=0x{so.Id:X8} at ({so.Frame.Origin.X:F2},{so.Frame.Origin.Y:F2},{so.Frame.Origin.Z:F2})"));
+        }
+    }
+
+    private static IEnumerable<uint> EnumerateCells(uint numCells)
+    {
+        for (uint low = 0x0100u; low < 0x0100u + numCells; low++)
+            yield return low;
+    }
+
+    /// <summary>
+    /// The tower's statics are SETUPS: 0x020005D8 ×4 (spiraling up — the stair
+    /// flights) + 0x020003F2 at the exact center (the user's "water barrel"
+    /// spot). Dump their part lists — if the [up-null] no-draw GfxObjs
+    /// (0x010002B4/0x010008A8) are parts here, the "missing stairs" are the
+    /// VISIBLE sibling parts failing, or the whole-part placement is off.
+    /// </summary>
+    [Theory]
+    [InlineData(0x020005D8u)]
+    [InlineData(0x020003F2u)]
+    public void DumpTowerStairSetups(uint setupId)
+    {
+        var datDir = ConformanceDats.ResolveDatDir();
+        if (datDir is null) { _out.WriteLine("dats unavailable — skipped"); return; }
+        using var dats = new DatCollection(datDir, DatAccessType.Read);
+
+        Assert.True(dats.Portal.TryGet<DatReaderWriter.DBObjs.Setup>(setupId, out var setup) && setup is not null,
+            $"Setup 0x{setupId:X8} not in portal dat");
+
+        _out.WriteLine($"=== Setup 0x{setupId:X8}: parts={setup!.Parts.Count} ===");
+        for (int i = 0; i < setup.Parts.Count; i++)
+        {
+            uint gfxId = setup.Parts[i];
+            string polyInfo = "MISSING";
+            if (dats.Portal.TryGet<DatReaderWriter.DBObjs.GfxObj>(gfxId, out var gfx) && gfx is not null)
+            {
+                int noDraw = 0;
+                foreach (var poly in gfx.Polygons.Values)
+                    if (poly.Stippling.HasFlag(DatReaderWriter.Enums.StipplingType.NoPos))
+                        noDraw++;
+                polyInfo = $"polys={gfx.Polygons.Count} noPos={noDraw} surfaces={gfx.Surfaces.Count}";
+            }
+            string frame = "";
+            if (setup.PlacementFrames.Count > 0)
+            {
+                var pf = setup.PlacementFrames.Values.First();
+                if (i < pf.Frames.Count)
+                {
+                    var f = pf.Frames[i];
+                    frame = FormattableString.Invariant(
+                        $" frame0=({f.Origin.X:F2},{f.Origin.Y:F2},{f.Origin.Z:F2})");
+                }
+            }
+            _out.WriteLine($"  part[{i}] gfx=0x{gfxId:X8} {polyInfo}{frame}");
+        }
+    }
+}