Complete Stage 1 on Standard difficulty or higher.
Complete Stage 2 on Standard difficulty or higher.
Complete Stage 3 on Standard difficulty or higher.
Complete Stage 4 on Standard difficulty or higher.
Complete Stage 5 on Standard difficulty or higher.
Complete the game on Advanced difficulty or higher.
Reach the Alien Queen without using any secondary weapons (Grenades, RPG, Flamethrower or Laser).
In a single game, use all secondary weaponss (Grenades, RPG, Flamethrower and Laser).
Reach 300k points.
Complete Stage 1 on Advanced difficulty using only the pistol. No machinegun or secondaries allowed.
Reach 600k points.
Reach 150k points, on Expert difficulty.