Bonus Artwork
At the first area where the game starts, there are two computers near the first save-game capsule. Use the talk buttom to see some art work and an enemy analysis list. Also, on the CD there is 4 BMP files, 2 page comic, and 2 posters.
Hitpoint Recovery
This only works if you are lower than 11 hit-points. If you are about to die and desperate to gain some energy, go to a staircase. Allow an enemy to hit you while you are on the staircase and you will recover up to 11 hit-points.