Find and Equip a Shotgun
Kill the first boss
Kill the second boss
On the 1st floor with Maj Wolf - kill all enemies without switching weapon
Kill the final boss
Reach the second floor without killing any enemies
Wipe out all enemies on the 1st floor without losing any life, using only Captain Ishii
Punch the Space Station boss
Kill your first 10 enemies
Empty an entire floor of enemies
Complete Docking Bay Level 1