The Phlogistinator is a primary weapon for the Pyro. It is a retro-futuristic ray gun with some metal parts colored either copper or silver depending on the team, and a team-colored canister stamped with the Dr. Grordbort crest.

It fires waves of energy that function identical to the Flamethrower's flames. These energy waves seem to appear across the Pyro's entire range simultaneously, despite the actual damage-causing particles needing a small travel time, resulting in an effect that can be deceiving to the eye.

There is a "Mmmph" bar that fills up from dealing fire damage, such as Flamethrower (Afterburn counts) and Flare Gun (critical flare counts as fire damage). It takes 225 damage to fill it up, and upon taunting he will, for the duration of the taunt, have a 75% damage resistance and taunt kills won't kill. This takes about 2 seconds. After this, the damage resistance is lost and the player gets a 10 second crit-boost for his primary weapon. The "Mmmph" bar cannot be charged while it is draining. The crit-boost still counts if the player starts taunting but is pushed into air or water resulting in a longer crit boost time, as the crit boost time starts when the taunt starts but the player is unable to attack. The taunt also quickly fills the player's health.  

As a downside, this weapon has a 10% damage penalty, no Compression Blast, and no random critical hits. In Mann vs. Machine mode, it takes 1200 damage against robots to fill the meter and 3000 damage against tanks. All enemies killed by this weapon have a special death animation; they float up while disintegrating while team-colored particles surround them.

This weapon often gets a bad rap. Many Free-To-Plays say this weapon is "broken" and anyone who uses it is a "noob". While this weapon may be good, the stock flamethrower outshines it due to the lack of airblast.

Community content is available under CC-BY-SA unless otherwise noted.