Cheats
Pause the game, hold L1 + L2 + R1 + R2 and introduce:
Restore health: triangle, down, x, above.
Restore ammunition: x, down, triangle, above.
1.000 experience points: X, below (3).
Level 2 skills: Circle, right, circle, right.
Level 4 skills: triangle, up, triangle, above.
Level 6 skills: square, left, square, left.
Level 8: X (2) skills, below (2).
Invincible: triangle, square, x, circle.
Infinite projectiles: square, circle, x, triangle.
Devastating attacks: square (2), circle (2).
All combo improvements: triangle, circle, triangle, circle.
Small enemies: triangle (2), x (2).
Slow chamber: triangle, circle, x, square.