The user wants me to build a top-down alien shooter game using Phaser.js. The requirements are:
1. Use the pre-provided phaser.min.js (already in the current directory)
2. Single-page web app in index.html with inline CSS and JS
3. Move with WASD
4. Aim and fire at waves of advancing aliens
5. Health, score, and increasing difficulty
6. ONLY procedurally generated graphics (no external assets)
7. No external resources, CDNs, or network requests

I need to:
1. First check if phaser.min.js exists in the current directory
2. Create a complete index.html file with all the game logic

Let me start by checking the current directory and then create the game

Good, phaser.min.js is present. Now I need to create a complete top-down alien shooter game in a single index.html file. The requirements are:

1. Use Phaser (already available as phaser.min.js)
2. Single-page web app with all code in index.html
3. CSS in <style> tag, JS in <script> tag
4. No external resources - all graphics must be procedurally generated
5. WASD movement
6. Aim and fire at waves of advancing aliens
7. Health, score, and increasing difficulty
8. Load phaser.min.js with <script src="phaser.min.js"></script>

I'll create a complete game with:
- Player ship that moves with WASD
- Mouse aiming and clicking to shoot
- Waves of aliens that advance toward the player
- Health system for player
- Score system
- Increasing difficulty (more aliens, faster aliens, etc.)
- Procedurally generated graphics using Phaser's graphics API

Let me create this comprehensive game file.

The user asked me to build a top-down alien shooter game using Phaser with specific requirements:
1. Use the pre-provided phaser.min.js (which I confirmed exists)
2. Build it as a single-page web app in index.html
3. Use ONLY procedurally generated graphics (no external assets)
4. Move with WASD
5. Aim and fire at waves of advancing aliens
6. Include health, score, and increasing difficulty

I've created the index.html file with all the required features:
- WASD movement for the player
- Mouse aiming (player rotates towards pointer)
- Click to fire bullets
- Waves of aliens that advance toward the player
- Health system (player starts with 100 health, loses health when aliens reach bottom or hit player)
- Score system (increases when aliens are killed)
- Increasing difficulty (waves get harder with more aliens, faster aliens, shorter spawn times)
- All graphics are procedurally generated using Phaser's graphics API
- Particle effects for explosions
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