1 weapon mode:
To get 1 weapon mode, you have to beat the game once in Brand New Fear File with any ending in hard mode and get 10 Stars.
All Weapon Mode:
Beat the game with any ending on hard with the 1 weapon mode.
Eileen's Sub-Machine Gun:
To unlock Eileen's Sub-machine gun beat the game in hard in a Brand New Fear File and get at least 9 stars. If done correctly: You can get the Sub-machine gun in your first visit of the Apartment World in room 102.
Chainsaw:
Beat the game once in any mode and Chainsaw will be available at the Forest (First) in the area where there's a car.
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