diff --git a/README.md b/README.md
index e155b29..ff1975d 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,11 @@
 # Sokoban
 
-A browser-based Sokoban game built with Phaser 3 and Vite, shipping 100 Microban levels by David W. Skinner.
+My from-scratch Sokoban game, built with Phaser 3 and Vite. The engine, UI, level parser, and progression system are all my own implementation. The puzzle layouts themselves come from David W. Skinner's freely distributable **Microban** set — I'm not reusing any of his code, only his level designs.
 
 Play: [https://tiennm99.github.io/sokoban/](https://tiennm99.github.io/sokoban/)
 
 ## Features
-- **100 solvable puzzles** from the Microban set (beginner-friendly, concept-focused).
+- **100 solvable puzzles** using level layouts from the Microban set (beginner-friendly, concept-focused).
 - **Paginated level select** with progress tracking and best-move record per level.
 - **Controls**: arrow keys or WASD. `U` / `Z` to undo, `R` to restart, `Esc` for menu.
 - **Undo history**, live move counter, animated moves.
@@ -33,7 +33,8 @@ See [`docs/codebase-summary.md`](docs/codebase-summary.md).
 - [`docs/project-changelog.md`](docs/project-changelog.md) — release notes.
 
 ## Credits
-- Puzzles: **Microban** by David W. Skinner (April 2000). Freely distributable with credit. Original site: http://users.bentonrea.com/~sasquatch/sokoban/
+- Puzzle layouts: **Microban** level set by David W. Skinner (April 2000). Freely distributable with credit. Original site: http://users.bentonrea.com/~sasquatch/sokoban/
+- Game code: tiennm99 (with AI pair-programming from Claude).
 - Engine: [Phaser 3](https://phaser.io/).
 
 ## License
diff --git a/docs/project-overview-pdr.md b/docs/project-overview-pdr.md
index 19b4a23..b5e6b3b 100644
--- a/docs/project-overview-pdr.md
+++ b/docs/project-overview-pdr.md
@@ -1,7 +1,7 @@
 # Sokoban — Product Development Record
 
 ## What it is
-Browser-based Sokoban puzzle game. 100 solvable Microban levels (David W. Skinner, freely distributable), Phaser 3 + Vite, deployed to GitHub Pages.
+A from-scratch Sokoban implementation by tiennm99. Phaser 3 + Vite, deployed to GitHub Pages. The engine, UI, parser, and progression system are original code. Puzzle layouts come from David W. Skinner's freely distributable **Microban** set (100 of his puzzles shipped) — layouts only, no code reused from Skinner's own programs.
 
 ## Goals
 - Clean, beginner-friendly Sokoban that runs in any modern browser with no install.
@@ -24,5 +24,6 @@ Casual puzzle fans, Sokoban beginners. Microban set chosen specifically because
 - Runs smoothly on desktop browsers at 1024×768 canvas (scaled responsively).
 
 ## Credits
-- Puzzles: Microban by David W. Skinner (April 2000). Used per the collection's free-distribution terms with credit.
+- Puzzle layouts: Microban by David W. Skinner (April 2000). Used per the collection's free-distribution terms with credit. Only the level designs — none of Skinner's code.
+- Game code: tiennm99 (with AI pair-programming from Claude).
 - Engine: Phaser 3.
diff --git a/src/game/data/microban-levels.js b/src/game/data/microban-levels.js
index 762420b..5a7f07e 100644
--- a/src/game/data/microban-levels.js
+++ b/src/game/data/microban-levels.js
@@ -1,7 +1,9 @@
 /**
- * Microban level set by David W. Skinner (April 2000, 155 puzzles).
- * Freely distributable with credit. First 100 levels shipped here — small,
- * concept-focused puzzles that are great for beginners and still interesting.
+ * Puzzle layouts from the Microban level set by David W. Skinner
+ * (April 2000, 155 puzzles, freely distributable with credit).
+ * First 100 layouts shipped here — small, concept-focused puzzles.
+ * Only the level designs are borrowed; the parser, renderer, and engine
+ * are original code written for this project.
  * Source: http://users.bentonrea.com/~sasquatch/sokoban/
  *
  * Format: XSB
diff --git a/src/game/scenes/menu-scene.js b/src/game/scenes/menu-scene.js
index e8009f6..5c2515c 100644
--- a/src/game/scenes/menu-scene.js
+++ b/src/game/scenes/menu-scene.js
@@ -19,7 +19,7 @@ export default class MenuScene extends Phaser.Scene {
         const cy = this.cameras.main.centerY;
 
         this.add.text(cx, cy - 200, 'SOKOBAN', FONTS.title).setOrigin(0.5);
-        this.add.text(cx, cy - 130, '100 Microban puzzles', FONTS.subtitle).setOrigin(0.5);
+        this.add.text(cx, cy - 130, '100 puzzles to solve', FONTS.subtitle).setOrigin(0.5);
 
         createButton(this, cx, cy - 20, 'PLAY', () => this.scene.start('LevelScene'), { width: 240, height: 64 });
 
@@ -33,6 +33,6 @@ export default class MenuScene extends Phaser.Scene {
         ].join('\n');
         this.add.text(cx, cy + 170, hints, { ...FONTS.small, align: 'center' }).setOrigin(0.5);
 
-        this.add.text(cx, this.cameras.main.height - 24, 'Microban puzzles by David W. Skinner', FONTS.small).setOrigin(0.5);
+        this.add.text(cx, this.cameras.main.height - 24, 'Level layouts from Microban by David W. Skinner', FONTS.small).setOrigin(0.5);
     }
 }