The user wants me to build a top-down alien shooter game using Phaser.js. Let me plan this out:

1. First, I should check what's in the current directory to see the phaser.min.js file
2. Then create a single HTML file with:
   - CSS for styling
   - JavaScript game logic using Phaser
   - Procedurally generated graphics (using Phaser's Graphics object to draw sprites programmatically)
   - WASD movement
   - Aim and fire mechanics
   - Wave-based alien spawning
   - Health system
   - Score system
   - Increasing difficulty

Let me start by checking the directory and the phaser.min.js file.

Good, I can see phaser.min.js is present. Now I'll create the index.html file with the game. Let me build a complete top-down alien shooter with:

1. Player movement with WASD
2. Mouse aiming and shooting
3. Wave-based alien spawning with increasing difficulty
4. Health system
5. Score tracking
6. Procedurally generated graphics (using Phaser's Graphics to draw sprites)

I'll create:
- Player ship (drawn with graphics)
- Bullets (drawn with graphics)
- Aliens (drawn with graphics, various colors)
- Background (procedural starfield)
- UI for health, score, wave info

I've created the index.html file. Let me verify it exists and check its basic structure.

The index.html file has been created. Let me verify the structure is correct by reading the beginning to make sure it loads phaser.min.js properly.

The file looks good. It loads phaser.min.js locally, not from CDN. The game should be complete. Let me summarize what was created.