Hers what you need to do to get all 5 endings.

I know this is somewhat an older game, but I just learned a new trick. Here's what to do. You must have unlocked and select the cop uniform. When Alex first gets home, grab the pistol as usual by the bunk bed. Then proceed with the game. After the 2nd visit from the crypt, go back to the bedroom again grab the Lazer Pistol before darkness falls (I keep using it the whole time except when you have to use an axe or something to open doors). At the police station, all of Alex's weapons are stripped... BUT when Alex gets to the underground room, his pistol is still in his posession. That saves a lot of time killing at least 10 Order Soldiers and Curtis. It works for me.

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