diff --git a/docs/plans/2026-07-27-vulkan-campaign.md b/docs/plans/2026-07-27-vulkan-campaign.md
index 54dc7bf6..f62a878c 100644
--- a/docs/plans/2026-07-27-vulkan-campaign.md
+++ b/docs/plans/2026-07-27-vulkan-campaign.md
@@ -576,6 +576,7 @@ tenth pair with no consumer at all; see the V6e report.
 | **V6h** ✅ | **The Vulkan composition host**, specified by §5.5.9 and reported in §5.5.10. `ACDREAM_RENDER_BACKEND=vulkan` runs the real `GameWindow` composition — DAT load, streaming, camera, entity table, session, and the real retained `UiHost` through the RHI — with no world renderers. Three seams: the already-generic platform acquisition now publishes a `GameWindowGraphics`; `VulkanHostInputCameraCompositionFactory` is the host-phase fork; the frame root gains a Vulkan arm. `VulkanBringUpHost` is reduced to the capability-probe harness over the extracted `VulkanGraphicsContext`. | offline Vulkan launch reaching the real composition with the client's own UI captured, one validation-layer run at 0 errors / 0 warnings, converging ownership ledger, App tests 4,075/3, complete Release suite 9,138/5, GL offline pixel gate 1.78e-05 |
 | **V6i** ✅ | **The world arm's prerequisites**, in two parts. **V6i-1** (`df6e2a79`, reported in §5.5.12) closed §5.5.8's one-binding-two-buffers hazard with one descriptor-set pair per renderer scope, derived from the descriptor state rather than declared, and measured the ordered remainder list the world arm still needed. **V6i-2** (reported in §5.5.13) took items 1, 2 and 6 of that list in three gated commits: **1** the `TerrainClip` descriptor-set fix plus set 1's missing bindings 2 and 4, proven by `spirv-dis` and now gated by a SPIR-V-reading contract test (`f7344758`); **2** world texture CREATION crosses to `IGpuTexture` — `IWorldTextureArray` over `TextureAtlasManager`/`ManagedGLTextureArray`, `TerrainAtlas`'s second construction path, and `ICompositeTextureArrayBackend`'s RHI arm — with the Vulkan arm exercised at startup (`c8d0f70b`); **3** `IMeshPipelineDevice` decouples `ObjectMeshManager`/`WbMeshAdapter` from `OpenGLGraphicsDevice`. **Items 3–5 — the submission arms, `RetailPViewPassExecutor`, and the pass-structure merge — are the next slice's.** | pixel gate per commit (3.02e-05, 3.20e-05, 1.60e-05 vs `0ca802cd`), App tests 4,109/3 and complete Release suite 9,172/5, 3/3 desktop-witness connected run at commits 2 and 3, one validation-layer Vulkan run per commit |
 | **V6i-3** | **The mesh pipeline runs on both arms, and the Vulkan frame gets a world pass**, reported in §5.5.14. Two commits: **1** `GlobalMeshBuffer` takes `GL?` and publishes `VertexStore`/`IndexStore`, `ObjectMeshManager`'s `RequireGl` narrows to the unreachable legacy upload, `VulkanMeshPipelineDevice` is `IMeshPipelineDevice`'s second implementation, and `NullWbMeshAdapter` is deleted (`fe8abacf`); **2** the clear merges into the world pass with `Store = Resolve` and descriptor sets bind at draw time (`887de4ae`). **The world renderers' submission arms and `RetailPViewPassExecutor` did NOT land** — §5.5.14 enumerates what they still need. | pixel gate per commit (4.44e-05, 3.73e-05 vs `579e0b7f`), App tests 4,112/3, one 3/3 desktop-witness connected run at HEAD, one validation-layer Vulkan run per commit, and a bit-identical (0/921,600) Vulkan capture across the pass merge |
+| **V6j** ✅ | **The world arm, whole**, reported in §5.5.15. Two commits: **1** `VulkanViewportMapping` stops inverting the front face — the world arm is the mapping's first culling consumer and measured that the inversion culls terrain outright and turns every closed shell inside-out (`81fe5e1b`); **2** the three renderers' RHI submission arms as a SECOND arm per §5.5.6, both pass executors made backend-neutral behind `IWorldPassSurface`, `VulkanWorldPassScope` publishing the frame's one pass, `WorldFrameSections` carrying the three frame-global sections, and the composition that reaches them (`f84eef32`). **`ACDREAM_RENDER_BACKEND=vulkan` renders Dereth**: terrain, blending, roads, water, statics, scenery and the retained UI. Sky stays fog until V4f. | GL pixel gate 5.50e-05 vs `847f14ae` with a characterised 12–31 px noise distribution, App tests 4,112/3, complete Release suite 9,175/5, GL connected `-Runs 3` at 3/3 on both columns, one validation-layer Vulkan run at 0 errors / 0 warnings, and the world PNG inspected in §5.5.15 |
 | **V7** | GL-versus-Vulkan differential: `tools/run-backend-differential-gate.ps1`, strict paired-PNG compare, divergences fixed in the Vulkan backend only, then lifecycle + R6 soak natively on Vulkan, one validation-layer-clean run, one RenderDoc capture. **Milestone: parity.** | every differential checkpoint passes; both connected routes green on VK |
 | **V8** | Perf gate on the RX 9070 XT, uncapped, both backends, same route. | §2 acceptance table; parity is the floor |
 | **V9** | Linux + CI: X11/Wayland surfaces; a `linux-vulkan` job on lavapipe (probe accepts on a real 1.3 software device, a short real render under xvfb, forced-unsupported → exit 4, `.spv` freshness). Physical Linux GPU row deferred post-cutover, as for Slice L. | CI green including the new job |
@@ -1857,6 +1858,134 @@ submission arms and `RetailPViewPassExecutor`, which §5.5.12 item 3 established
 is on the critical path because the offline gate's scene has buildings and
 therefore takes the PView route.
 
+#### 5.5.15 V6j (2026-07-28): the world arm lands, and Dereth draws on Vulkan
+
+§5.5.14's remainder — the three renderers' submission arms,
+`RetailPViewPassExecutor`, and the frame-global sections — is done.
+**`ACDREAM_RENDER_BACKEND=vulkan` renders the offline scene: terrain with blended
+textures and road overlays, the water edge, static world meshes, procedural
+scenery, and the complete retained UI**, from the same camera as the GL capture
+(`artifacts/v6j-vk2` against `artifacts/v6j-head2`). Sky is still the atmosphere
+fog clear, because `SkyRenderer` is raw GL until V4f.
+
+Three predecessors stopped at this unit under §7.1 rule 3. It landed as one slice
+in two commits, because the rule is satisfied at SLICE granularity: the first
+commit's piece is unreachable on its own and the second wires it and exercises it.
+
+**1. The winding inversion was wrong, and nothing had ever asked** (`81fe5e1b`).
+`VulkanViewportMapping` has inverted the front face since V6c, on the standard
+negative-viewport argument. Every Vulkan consumer through V6i declares
+`Cull = GpuCullMode.None`, so the mapping had never decided a fragment. The world
+arm is its first culling consumer and falsified it twice on one frame: terrain —
+the one single-sided surface acdream draws, `FrontFace(Ccw)` + `Cull(Back)` per
+`ACRender::landPolysDraw`'s eye-side predicate — vanished entirely while issuing
+190 multi-draw commands against 625 loaded landblocks, and every closed building
+shell rendered inside-out with its front wall culled and its interior beams
+visible through the gap. The identity mapping restores both at once. Two
+independent surfaces, one change. The viewport flip itself is untouched and still
+correct; what goes is the claim that a winding inversion travels with it.
+
+**Worth generalising**: this is the third defect this campaign has found in a path
+that compiled, validated clean, and had a test — because the test asserted the
+behaviour rather than the requirement, and no consumer exercised it. §5.5.12's
+descriptor layouts and §5.5.13's `TerrainClip` set were the first two.
+
+**2. The world arm** (`f84eef32`). V4c's and V4d-2's content returns as a SECOND
+arm, per §5.5.6's option (B): the GL arm issues the same statements in the same
+order, and the encoder arm lives in three `.Rhi.cs` partials entered by one branch
+per submission site. Three differences from V4c, each because the tree moved —
+no binding-9 table (V4t put the slot on the device; Vulkan binds set 2), pipelines
+carry the device's sample count, and **no renderer opens a pass**.
+
+`VulkanWorldScenePhase` opens the frame's one backbuffer pass, publishes the
+encoder on `VulkanWorldPassScope` for exactly the span of the inner
+`WorldSceneRenderer`, and every renderer borrows it — §5.5.14 item 1's shape,
+built as specified. The three frame-global sections are PUBLISHED on
+`WorldFrameSections` and each renderer binds them inside the pass after its own
+binds (item 2). The interior depth clear is `vkCmdClearAttachments` through the
+scope (item 3); clip distances are no-ops (item 4); the collision-wireframe
+`DebugLineRenderer` is composed null (item 7).
+
+**Both pass executors became backend-neutral rather than gaining twins.** That is
+the one place this slice diverged from §5.5.14's sketch, and it is why the slice
+was tractable. Everything those two classes do is delegation to a renderer except
+four concerns — the clip-frame publication, the doorway scissor,
+`gl_ClipDistance` enablement and the interior depth clear — so those moved behind
+`IWorldPassSurface` and retail's ordering, which is what the classes are actually
+for, is written once for both backends. `RetailPViewPassExecutor` was on the
+critical path precisely because the gate's scene has buildings (§5.5.12 item 3);
+it now serves both arms unchanged.
+
+**The A8 question is answered.** §5.5.13 and §5.5.14 asked what happens to the
+Phase A8 `CullMode.Landblock → None` override the moment world materials draw on
+a second backend. It carried over verbatim and is still load-bearing:
+`EnvCellRenderer`'s Vulkan arm applies the same rewrite, for the same reason, and
+the offline scene has no interior to disprove it with. The override is therefore
+neither vindicated nor retired by this slice — it is now a divergence with two
+consumers instead of one, and the dungeon pass in §5.1's checklist is what will
+settle it.
+
+**Gates.** Release build green. App tests **4,112 / 3 skips** — the unchanged
+baseline; complete Release suite **9,175 / 5**. Strict GL offline pixel gate
+against `847f14ae`: **5.50e-05** (31 differing pixels of 563,200), inside the
+documented 9–31 band and 18x under the threshold. Characterised rather than
+accepted, because 31 is the band's top:
+
+```
+cross-commit (847f14ae vs V6j):  21, 29, 31
+same-commit  (V6j vs V6j):       12, 20
+maximumChannelDelta, all pairs:  46-52
+```
+
+The max delta is 46–52 in every comparison INCLUDING the pure same-commit
+controls, so the few large-delta pixels are a property of the capture. A
+cross-commit pair at 21 against a same-commit pair at 20 is not what a systematic
+shift looks like — a real one floors every cross-commit comparison above every
+same-commit one. GL connected `tools/run-repeat-connected-gate.ps1 -Runs 3`:
+**3/3 RENDERED** on the desktop witness and 3/3 on the client capture. One offline
+Vulkan run with `VK_LAYER_KHRONOS_validation` **proven inserted by the loader**:
+**zero validation errors, zero warnings**, a captured world frame, graceful close.
+`tools/run-offline-vulkan-capture.ps1` is the new script that produces it.
+
+**The Dereth PNG, inspected honestly.** Right: terrain geometry, terrain blending
+and its T-code transitions, road overlays, the water edge and its shoreline,
+static world meshes with correct silhouettes and closed shells, procedural
+scenery, per-instance lighting, the fog colour, and the complete retained UI
+including the radar. The frame matches the GL capture's framing and content
+element for element below the horizon.
+
+Wrong, and each already owned by a later slice: **the sky is flat fog** (V4f —
+`SkyRenderer` is raw GL, so there is no dome, no sun, no cloud sheet, no horizon
+band); **no particles** (V4e); **no paperdoll or appraisal viewport and no portal
+depth mask** (V4g); **no GPU frame timings** (`NullRenderFrameGpuMeasurement`
+until V4h). None of these is a defect in this slice — they are the renderers it
+deliberately does not compose.
+
+**The V7 defect list — what a differential must not be run against yet.**
+
+1. **Sky, particles, viewports, portal mask** — absent, not wrong. V4e/V4f/V4g.
+2. **§5.4's `Target: null` divergence is still live on GL.** V7 must not run until
+   V4g/V4h remove it, or it surfaces as an entire viewport on the wrong surface —
+   unchanged from §5.4's own warning, and now more binding because both backends
+   draw a world.
+3. **`EnvCellRenderer`'s Vulkan arm is unproven by anything automated.** The
+   offline scene has no interior. This is V4c's exact debt, restated on the new
+   backend.
+4. **The deferred-alpha path and the doorway scissor are unexercised** in the
+   offline scene: no alpha queue collects and no doorway slice is assembled, so
+   `DrawPreparedAlphaBatch`'s Vulkan arm and `RhiWorldPassSurface.BeginScissor`
+   have run zero times.
+5. **MSAA must be forced off for the differential**, as §5.1 already states —
+   sample positions are not specified across implementations, and the world
+   pipelines now genuinely differ in sample count from the UI's.
+6. **Bindings 4, 6, 7 and 8 cost a descriptor write per draw** (§5.5.14 item 5).
+   Correct and bounded, and a V8 perf item rather than a correctness one, but the
+   arena's `ScopeCount` is the number to watch.
+
+**What this slice does NOT claim.** It has not run connected on Vulkan, it has not
+been seen by the user, and no dungeon, portal, paperdoll or spell effect has been
+drawn on it. The milestone "full game frame on Vulkan" needs V4e–V4g behind it.
+
 ### 5.4 The null-target `BeginPass` divergence (V4c) — must be undone at V6
 
 V4c had to stop GL's `BeginPass` from binding framebuffer 0 when a pass declares