A stylised rocks and cliffs kit of 20 pieces for fantasy and adventure levels: angular columnar cliff walls (6 m sections that line up and overlap), a corner, tall spires, a natural arch, a ledge, a rocky ramp and a full range of boulders down to pebbles. Upward facets carry moss and grass automatically, every piece has three LODs and one convex collision hull per rock chunk.

What's included (20 pieces, each with LOD0 / LOD1 / LOD2 + collision)

• Cliffs: cliff_wall_a (6 m), cliff_wall_b (8 m), cliff_wall_low (3 m), cliff_wall_warm (sandstone), cliff_corner
• Features: spire_tall, spire_short, arch, ledge, ramp
• Boulders and scatter: boulder_large_a/b, boulder_medium_a/b, boulder_small_a/b, slab_a/b, pebbles, stepping_stones
• Formats: GLB, FBX, per-LOD Unreal FBX, OBJ/MTL + Blender source

Specs

• Real-world scale in metres (cliff walls 6 to 8 m tall, tall spire 7.7 m, arch 7 m wide)
• LOD0 138 to 1,568 triangles per piece, 12,688 for the whole kit; LOD1 ~45 %, LOD2 ~15 %
• 87 convex UCX hulls (one per rock chunk), so arches and overhangs keep their openings
• PBR metal/roughness: 4 tiling texture sets at 1024 px (albedo, normal GL + DX, roughness, metallic, AO, ORM), triplanar world-scale UVs
• All textures and meshes made procedurally by AssetLoom (no scans, no third-party content)

Conventions

Units: metres, real-world scale. Z-up in the .blend; GLB/FBX/OBJ exported Y-up (glTF convention).
Pivots: ground level (z = 0) at the base centre; rocks sink 4 to 25 cm below z = 0 so they sit into uneven terrain.
  Cliff walls: about 6 m wide along X (overlap neighbours by ~0.5 m), front face near y = 0, rock mass behind toward +Y.
  rck_ledge: back at y = 0 (push it into a cliff face), pivot at the back edge at top-surface height.
Hierarchy per piece: empty root <name> (the pivot) -> <name>_LOD0, <name>_LOD1, <name>_LOD2 and UCX_<name>_NN convex collision hulls (identity transforms).
LODs: LOD1 = 45 % and LOD2 = 15 % of the LOD0 triangles (fewer segments and bevels, small details removed); same materials.
Collision: UCX_ hulls are convex and closed (Unreal simple collision naming); the GLBs name them UCX_<name>_NN-convcolonly for Godot.
Normals: smooth groups split by angle + area-weighted custom normals (exported). Meshes are triangulated.
UVs: world-scale projections per part (planar, cylindrical or triplanar) with tiling PBR textures; no lightmap UV2 (let the engine generate one).
Materials (4): rck_grass, rck_moss, rck_rock, rck_rock_warm.
Textures: <set>_albedo, _normal-gl (OpenGL: Unity, Godot, Blender), _normal-dx (DirectX: Unreal), _roughness, _metallic, _ao,
  _orm (R = AO, G = roughness, B = metallic). GLBs embed JPEG copies; FBX/OBJ reference ../textures/.
LOD1/LOD2 are collapse-decimated copies of LOD0 with re-projected triplanar UVs; UCX: one convex hull per rock chunk (largest 16).

Engine notes

• Unity (URP/HDRP/Built-in): import fbx/ + textures/. The _LOD0/_LOD1/LOD2 children build an LOD Group automatically. UCX meshes import as plain meshes:
• select them, remove the Mesh Renderer and add a Mesh Collider (Convex), or delete them and use primitive colliders. Set _normal-gl maps to Normal Map.
• Unreal Engine 5: import unreal/.fbx (mesh + UCX__NN hulls become its simple collision automatically; keep "Combine Meshes" on).
• Then Static Mesh Editor > LOD Settings > LOD Import > Import LOD Level 1/2 with unreal/_LOD1.fbx and _LOD2.fbx. Use _normal-dx and _orm.
• Godot 4: import glb/. Nodes ending in -convcolonly become StaticBody3D convex collision shapes; hide or delete the _LOD1/_LOD2 nodes
• (Godot generates its own mesh LODs) or drive them with visibility ranges.
• Blender: open the .blend (LOD1/LOD2 and UCX objects are hidden children of each piece) or import any GLB/FBX/OBJ. OBJ files contain LOD0 only.

Headless Blender check

• All 20 pieces re-imported from the shipped files: GLB 20/20 and FBX 20/20 with 3 LODs + every UCX hull, Unreal FBX sets 20/20, OBJ 20/20; every PBR map resolved; triangle counts match the build: yes.
• 0 loose vertices/edges, 0 degenerate faces, 0 open edges, 0 flipped-normal edges across all LODs; 0 floating parts.
• 87 UCX hulls, all convex and closed.