Having trouble seeing? Download the flashlight pistol mod: http://dlx.gamespot.com/pc/doom3/moreinfo_6104168.html

Subjectively, I have not yet tried this out. What I recommend trying if you do know wish to use this is to try setting the flashlight bind key to F or some other close key so you can easily switch between your flashlight and your previously used weapon. Works like a charm.

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