Complete the tutorial.

Destroy 20 tanks.

Destroy 10 computers.

Open the doors using two different kinds of cards.

Squat 10 times.

Destroy 20 robots.

Turn off the laser.

Collect 10 dog-tags.

Shoot 1000 bullets with a rifle.

Die three times.

Use the Angry Mode 3 times.

Shoot 100 bullets from the gun.

Destroy 10 jelly-aliens.

Shoot 50 rounds with a shotgun.

Destroy 10 ugly-eye-aliens.

Die in the poisonous fumes.

Use the rocket launcher 10 times

Destroy 50 bombs.

Play and finish the game in hard mode.

Finish the game in ultra mode.

Squat 30 times while flying.

Shoot 10 000 rounds from the rifle.

Die 100 times.

Use hard restar option once

Use reset level option once.

Read the manual.

Use Angry Mode with Auto-Angry option.

Turn down the music to zero.

Complete the game.

Find all the secrets.