Spy
The Spy is a suave backstabbing rogue that has the ability to insta-kill any class in the game with their knife. Spies are valued in that they can get important picks through the manipulation and deception of the enemy team. The Spy arguably has the worst direct combat ability, as it is solely designed to only get one or two kills at a time. As a pick class, the Spy will usually target the enemy Demoman, Heavy or Medic and either get the Medic to pop or drop his Übercharge. The Spy is also capable of incapacitating and destroying the Engineer's buildings.
6v6
Main Article: Spy (6v6)
In 6v6, the Spy is considered an offclass due to his unreliable damage output and weakness, if a Spy is played they will usually only get one chance at getting a pick. Because of this, the Spy is rarely used and will most often target the enemy Medic or Demoman to get a pick worth more than his own life. A team might use a Spy when the enemy Medic has a large advantage and they want to kill him or during a stalemate when the Spy will break it by getting an important pick.
Highlander
Main Article: Spy (Highlander)
In Highlander, the Spy is often used to pick the enemy Medic, Heavy, Demoman, Sniper, and Engineer. Spies in Highlander must be aware that the enemy team has a full-time Pyro and is spychecking more often, leaving the Spy with less opportunities for picks.
The Spy is also the best scouting class in the game, providing invaluable information for his team. He can find how far along a Medic is to fully charging his ubercharge, where the enemy team is located, and in what direction they are moving towards in the safety provided by his watches.
Trickstabs
When spotted or confronted by an enemy, a spy is almost always put at a disadvantage, due to his low damage output on primaries. In times of need, Spies may use trickstabs to place themselves behinds the enemy, for a very risky stab. The are a multitude of ways to do so. For an example, the most popular trickstab involves jumping over an elevated area (ex: stairs) to get over the enemy's head and stab them from above.
Allowed Weapons
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