diff --git a/src/commands/set-box-brush-face-climbable-command.ts b/src/commands/set-box-brush-face-climbable-command.ts
new file mode 100644
index 00000000..50f6cac5
--- /dev/null
+++ b/src/commands/set-box-brush-face-climbable-command.ts
@@ -0,0 +1,91 @@
+import type { ToolMode } from "../core/tool-mode";
+import { createOpaqueId } from "../core/ids";
+import type { EditorSelection } from "../core/selection";
+import type { WhiteboxFaceId } from "../document/brushes";
+
+import {
+  cloneSelectionForCommand,
+  getBoxBrushFaceOrThrow,
+  replaceBoxBrushFace,
+  setSingleBrushFaceSelection
+} from "./brush-command-helpers";
+import type { EditorCommand } from "./command";
+
+interface SetBoxBrushFaceClimbableCommandOptions {
+  brushId: string;
+  faceId: WhiteboxFaceId;
+  climbable: boolean;
+}
+
+export function createSetBoxBrushFaceClimbableCommand(
+  options: SetBoxBrushFaceClimbableCommandOptions
+): EditorCommand {
+  let previousClimbable: boolean | null = null;
+  let previousSelection: EditorSelection | null = null;
+  let previousToolMode: ToolMode | null = null;
+
+  return {
+    id: createOpaqueId("command"),
+    label: options.climbable
+      ? `Mark ${options.faceId} face climbable`
+      : `Clear ${options.faceId} face climbable`,
+    execute(context) {
+      const currentDocument = context.getDocument();
+      const currentFace = getBoxBrushFaceOrThrow(
+        currentDocument,
+        options.brushId,
+        options.faceId
+      );
+
+      if (previousClimbable === null) {
+        previousClimbable = currentFace.climbable;
+      }
+
+      if (previousSelection === null) {
+        previousSelection = cloneSelectionForCommand(context.getSelection());
+      }
+
+      if (previousToolMode === null) {
+        previousToolMode = context.getToolMode();
+      }
+
+      context.setDocument(
+        replaceBoxBrushFace(currentDocument, options.brushId, options.faceId, {
+          ...currentFace,
+          climbable: options.climbable
+        })
+      );
+      context.setSelection(
+        setSingleBrushFaceSelection(options.brushId, options.faceId)
+      );
+      context.setToolMode("select");
+    },
+    undo(context) {
+      if (previousClimbable === null) {
+        return;
+      }
+
+      const currentDocument = context.getDocument();
+      const currentFace = getBoxBrushFaceOrThrow(
+        currentDocument,
+        options.brushId,
+        options.faceId
+      );
+
+      context.setDocument(
+        replaceBoxBrushFace(currentDocument, options.brushId, options.faceId, {
+          ...currentFace,
+          climbable: previousClimbable
+        })
+      );
+
+      if (previousSelection !== null) {
+        context.setSelection(previousSelection);
+      }
+
+      if (previousToolMode !== null) {
+        context.setToolMode(previousToolMode);
+      }
+    }
+  };
+}
diff --git a/src/document/migrate-scene-document.ts b/src/document/migrate-scene-document.ts
index 4dc017fc..6a01f7dc 100644
--- a/src/document/migrate-scene-document.ts
+++ b/src/document/migrate-scene-document.ts
@@ -244,6 +244,7 @@ import {
   DAWN_DUSK_BACKGROUND_IMAGE_SCENE_DOCUMENT_VERSION,
   WHITEBOX_PRIMITIVES_SCENE_DOCUMENT_VERSION,
   WHITEBOX_BEVEL_SCENE_DOCUMENT_VERSION,
+  WHITEBOX_FACE_CLIMBABLE_SCENE_DOCUMENT_VERSION,
   WHITEBOX_BOX_VOLUME_SCENE_DOCUMENT_VERSION,
   WHITEBOX_FLOAT_TRANSFORM_SCENE_DOCUMENT_VERSION,
   WHITEBOX_GEOMETRY_SCENE_DOCUMENT_VERSION,
@@ -2475,7 +2476,8 @@ function readBrushFace(
     uv:
       value.uv === undefined && allowMissingUvState
         ? createDefaultFaceUvState()
-        : readFaceUvState(value.uv, `${label}.uv`)
+        : readFaceUvState(value.uv, `${label}.uv`),
+    climbable: readOptionalBoolean(value.climbable, `${label}.climbable`, false)
   };
 }
 
@@ -5704,6 +5706,7 @@ export function migrateSceneDocument(source: unknown): SceneDocument {
     source.version !== GOD_RAYS_SOURCE_SIZE_SCENE_DOCUMENT_VERSION &&
     source.version !== ATMOSPHERE_POLISH_SCENE_DOCUMENT_VERSION &&
     source.version !== SCENE_DOCUMENT_VERSION &&
+    source.version !== WHITEBOX_FACE_CLIMBABLE_SCENE_DOCUMENT_VERSION &&
     source.version !== FOLLOW_ACTOR_PATH_SMOOTH_SCENE_DOCUMENT_VERSION
   ) {
     throw new Error(
diff --git a/src/document/scene-document-validation.ts b/src/document/scene-document-validation.ts
index 2574e21d..320c1559 100644
--- a/src/document/scene-document-validation.ts
+++ b/src/document/scene-document-validation.ts
@@ -6874,7 +6874,21 @@ export function validateSceneDocument(
     }
 
     for (const faceId of getBrushFaceIds(brush)) {
-      const materialId = brush.faces[faceId].materialId;
+      const face = brush.faces[faceId];
+
+      if (face === undefined) {
+        diagnostics.push(
+          createDiagnostic(
+            "error",
+            "missing-brush-face",
+            `Whitebox face ${faceId} must exist in brush face data.`,
+            `${path}.faces.${faceId}`
+          )
+        );
+        continue;
+      }
+
+      const materialId = face.materialId;
 
       if (materialId !== null && document.materials[materialId] === undefined) {
         diagnostics.push(
@@ -6886,6 +6900,17 @@ export function validateSceneDocument(
           )
         );
       }
+
+      if (!isBoolean(face.climbable)) {
+        diagnostics.push(
+          createDiagnostic(
+            "error",
+            "invalid-brush-face-climbable",
+            "Whitebox face climbable must remain a boolean.",
+            `${path}.faces.${faceId}.climbable`
+          )
+        );
+      }
     }
 
     const volume = brush.volume as Record<string, unknown>;
diff --git a/src/document/scene-document.ts b/src/document/scene-document.ts
index 3ebd5fed..3f44e920 100644
--- a/src/document/scene-document.ts
+++ b/src/document/scene-document.ts
@@ -29,7 +29,8 @@ import {
 } from "../sequencer/project-sequences";
 import type { Terrain } from "./terrains";
 
-export const SCENE_DOCUMENT_VERSION = 89 as const;
+export const SCENE_DOCUMENT_VERSION = 90 as const;
+export const WHITEBOX_FACE_CLIMBABLE_SCENE_DOCUMENT_VERSION = 90 as const;
 export const GOD_RAYS_SOURCE_SIZE_SCENE_DOCUMENT_VERSION = 89 as const;
 export const ATMOSPHERE_POLISH_SCENE_DOCUMENT_VERSION = 88 as const;
 export const GOD_RAYS_SCENE_DOCUMENT_VERSION = 87 as const;