Pyro
The Pyro is an offclass in 6v6 and a main class in Highlander. The Pyro is a maniac firebug who wields a Flamethrower as its main weapon. Along with the ability to inflict burn damage and a relatively high damage output, the Pyro also has the airblast mechanic, which can neutralize an enemy's uber with ease.
In Sixes
Main Article: Pyro (6v6)
In 6v6, the Pyro is considered an offclass. Most commonly run when defending last, the Pyro's job is to neutralize the enemy team's uber through use of the airblast mechanic.
In Highlander
Main Article: Pyro (Highlander)
In Highlander, the Pyro is considered an offensive class. The Pyro's main job in Highlander is spychecking to neutralize the other team's Spy. It also has a job of displacing and neutralizing enemy ubers.