Flashlight

The flashlight is a weapon in Doom 3. Its default key is F (White for Xbox). Its main purpose is to light up dark corridors, although it can be used as a weapon at close range.

Ideal uses
The flashlight in lower levels can be used to attack zombies to conserve ammo. It has slightly shorter range than the fists when used in this way, but is about twice as powerful. Attacking an enemy stronger than an Imp is not recommended. On higher levels, the flashlight should be used to light up dark corridors only. Upon sight of an enemy, a more powerful weapon should be swapped out. The flashlight could also be used to attack corpses on the ground to check that it is dead so that it does not rise again as a zombie. In deathmatch, using the flashlight alerts other people to your whereabouts. The weapon is not included in the Xbox version's deathmatches.

Trivia

 * The Doomguy's inability to attach his flashlight to a weapon in the game is often a subject of parody.
 * The Flashlight is powered by a Static transfer supply, the exact explanation of how it works is not explained, but it could be possible it absorbs static electricity say from a user holding it, and converts it into usable energy, and probably would not function if attached to a weapon as it would drain.
 * As it uses the aforementioned powersauce it does not require any battery replacement, fortunately.
 * the Inability to use light while having a weapon out was done deliberately to heighten tension and anxiety in Doom, using the flashlight would leave people pretty defenseless against a surprise attack, while sticking to a weapon while in the dark leaves you equally vulnerable of being ambushed in the dark.