Don't destroy any glass panels in Chapter 2.

Devastate the opponent's body as much as possible!

Nail down the opponent's head with the Pitter.

Collect your first additional weapon.

Save all the Scientists through the campaign.

Enter the secret room in Chapter 4.

Finish the game with a final score below 62,000 and the last score digit not equal to zero.

Finish the campaign at any difficulty.

Finish a chapter without reloading with bullets in the chamber.

Lose all credits and die.

Kill 5 enemies in a row.

Kill 3 enemies in a row.

Kill a Scientist.