In the underwater level (Level 7), you'll find a secret area that's home to a massive alien boss. To access it, swim to the far right of the level and shoot the seaweed-covered wall. A hidden door will appear, leading you to the secret area.
In the underwater level (Level 7), you'll find a secret area that's home to a massive alien boss. To access it, swim to the far right of the level and shoot the seaweed-covered wall. A hidden door will appear, leading you to the secret area.