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The best glitch is the merging glitch, where you can have the projectiles from the current weapon, but the ammo count, firing type, and damage of the second weapon. Method: Hold Reload with the current weapon, and switch to the second weapon before releasing Reload. "Switch" means press 1/2/3/4, or pick up a gun from the ground. The Reload and the switch can happen simultaneously. Grenades do not do anything as a first weapon, and don't do anything interesting as a second weapon (fires first weapon once while throwing nade normally). Some favorites: Flaregun-Knife, BOZAR-Minigun, LAW-Knife, Gauss-Minigun (For BOZAR-Minigun you have to hold R, drop BOZAR, then walk over Minigun) To reiterate, the second weapon is how much ammo you have and how the ammo is being consumed (speed/amount), but the first weapon is how that is expressed, whether it be a single bullet, burst of bullets, or a rocket (or melee if you want to waste ammo like that).
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