SUBSTELLAR — Independent review of the next planning slice Review date: 6 October 2026, America/Edmonton Review scope: planning and documentation only; no mod development or image generation. STATUS The two new written specifications and their registers pass this independent design-data review. No unresolved content, arithmetic, reference, connection-coordinate, or dependency-cycle blocker was found. The rebuilt HTML also passes the independent prior-edition preservation audit, recorded in validation_planning_preservation.json. The preservation comparison confirms all 58 immutable prior source/DOCX/art files, all 2,556 earlier HTML anchors, all 1,337 earlier rendered source blocks in their original order, and all 1,337 corresponding search records are unchanged. All 23 original PNGs, 23 WebP display files, and seven SVGs remain byte-identical, with no new image files. The additions contribute 126 First Playable blocks and 103 Tier 1 model blocks, each represented in search. All source download targets are present. The edition now contains 44 chapters and 2,711 search records. Exact source-to-HTML verification is a separate complementary check performed by the primary document validator. This result does not establish that the mod, geometry, models, renderer, networking, persistence, recipes, or performance work in-game. No actual mod source project was available in the inspected task workspace. The plan states that limitation, requires inspection of the real project, and retains the user's explicit BUILD gate for implementation. The reviewer performed no browser preview or browser-policy workaround. SOURCES REVIEWED The review compared the new First Playable and Tier 1 model specifications with the retained creative foundation, full Old Valley chapters, controller and regional-activity rules, industrial capability bands and machine catalogue, the existing Tier 1 operational chapter, and the supplied-reference catalogue. REF09, REF10, and REF15 were also visually inspected for the manufacturing-station distinction and source labels. Earlier source files and art are preserved separately from the additions. FIRST PLAYABLE The opening preserves all five Old Valley chapter identities and their order. The scoped playable completes the guesthouse's essential repair, the authored crossing, and the quarry's useful baseline services. The first workshop service introduces Chapter 4 without claiming the grain mill, full service network, market preparations, or Chapter 5 market are complete. Personal building remains legitimate, while its relationship to authored chapter completion is explained. The three industrial functions keep their canonical identities: IND-M01 Carpenter and repair bench, IND-M07 Alloy hearth, and IND-M53 Hoist and lift installation. The first hoist is a cargo-only, fixed-landings variant. The bench is repaired once in the quarry work bay after crossing; guesthouse and crossing preparation use earlier ordinary methods. No circular material or chapter gate was found. Required crossing resources are available before the crossing; the bench and hearth do not require their own outputs; the initial quarry does not require the improved cradle; no market, electrical installation, deep realm, planetary resource, rare kill, mandatory flooded dive, or unique unrecoverable item is needed. Copperwash Channels remains the representative Shallows route, with a dry required return and clearly optional exploration. The six construction orders sum to 84 planks, 68 cobblestone, 14 iron ingots, eight clay balls, and four bronze fittings. Every detailed stage sum matches its parent order. The bronze order requires three copper ingots, one tin ingot, and one fuel item; the hearth fuel is included within the 16-item preparation allocation rather than charged twice. The combined solo envelope, iron substitute, and omitted-hearth subtraction reconcile correctly. Native conversion assumptions are clearly provisional and await the project audit. Construction bills are shared once. Preparation is explicitly a solo allowance, with each cooperative player requiring suitable personal equipment and provision. The hoist comparison uses six prepared walls plus one existing spare-fuel item: two actual occupied stacks, two baseline trips, and one upgraded trip. Both goods are preserved and returned, with no new consumed-input bill. Fourteen First Playable tasks form an acyclic dependency graph. Task, construction-order, recipe, and image-brief IDs resolve to the written specification; section references are present. The completion matrix includes physical route usefulness, custody, stage interruption, damage and repair, participant eligibility, two-player contribution, ordinary-simulation boundaries, and accessible feedback. TIER 1 MODELS AND IMPLEMENTATION The register contains exactly the twenty existing canonical Tier 1 asset/service roles, including all eight T1-M machines. No additional mandatory spacecraft, refinery, oxygen machine, beacon recipe, or manufacturing-station role is introduced. Navigation Chip / Guidance Chip and Assembly Station / Assembly Table remain explicit aliases. The nine-block Explorer, three-by-three body, five-by-five fin envelope, two-level airlocked cabin, and associated pad are proposed production defaults. Conflicting six-, nine-, and twelve-block references remain visible. The candidate requires actual fit review before final art. Its numerical lower and upper standing clearances both equal 2.125 blocks, and the nine-block craft translated upward by the half-block pad deck reaches pad-local Y 9.5. These calculations do not prove usable geometry with the actual player rig, closures, ladder, seat, equipment, cargo, or cameras. The shared coordinate frame, quarter-turn transforms, normal directions, and pad-to-craft translation are consistent. All 62 declared ports have valid known interface types and axis normals, lie within their host's stated visible envelope, and use unique IDs. The four pad couplers coincide with their translated craft ports with opposite mating normals at all four supported facings: 16 pair/facing checks passed. The initial draft's offset refinery and pad fuel sockets could not mate directly to a block-grid pipe. This was corrected with two explicitly bounded T1-M04 terminal-adapter variants. Their host endpoints, grid endpoints, neighboring pipe origins, normals, and occupied reservations are specified. Both interface ends agree at all four facings: 16 endpoint/facing checks passed. Their whole reservation must participate in placement and obstruction checks. They do not add a new machine or compulsory processing recipe. The assembly station is a small controller/jig linked to an explicit full-size vehicle berth. The first fabrication task includes the minimum registered pad foundation and empty berth; the later pad task adds complete services, console, cargo, and mission preparation. This prevents a hidden dependency cycle between the assembly operation and its output location. Vehicle stages, refitting, cargo and supply transfers retain one authoritative craft and real stock. Sixteen Tier 1 implementation tasks form an acyclic graph. Referenced assets, tasks, creative decisions, source sections, and REF01–REF15 evidence entries resolve. Final integrated verification depends on both the functional expedition and the final animation/art integration; the early prototype voyage can still occur before final textures. Only the real-project inspection is marked as not requiring BUILD authorization. The first complete lunar mission retains a working airlocked Explorer cabin, Earth-carried EQ25 shelter and actual supplies/reserves. Shelter commissioning precedes the first committed underground descent. Local lunar production is not a bootstrap dependency. Orbital rehearsal uses its own valid manifest. Regional production, construction, consumption and events pause only under the established eligible-participant boundaries, while occupied remote habitats and ordinary Minecraft systems retain their stated behaviour. The first lunar arrival explicitly uses surveyed natural ground. Its contact plane is the Explorer origin without the Earth pad's half-block translation. No prebuilt lunar pad, refinery, or external console is required; carried supplies and onboard controls support return. The actual support geometry and acceptable ground slope remain part of the later measured fit check. TWO LATER CREATIVE REVIEWS T1-DEC01: approve or revise the measured Explorer/cabin scale after the fit evidence is available. T1-DEC02: confirm the smaller Part Fabrication Table and broader Rocket Assembly Station distinction before final production models. These are review points before final asset production, not blockers to finishing the present planning document. Other dimensions, quantities, and interface choices are identified as proposed defaults subject to inspection and testing. ARTWORK SCOPE Zero image-generation calls are made in this planning slice. The two planned future boards are the Old Valley opening and the first workshop/construction states. Tier 1 first uses the existing confirmed artwork; unresolved production views remain named later work. Tier 2 and Tier 3 remain at the supplied overview level. EVIDENCE FILES validation_planning_registers.json — independent arithmetic, ID, port, adapter, headroom, and task-DAG checks. validation_planning_preservation.json — prior-edition source, anchor, search, and artwork comparison after rebuild. validate_planning_slice.py — read-only prior-edition comparison checker.