Any player should tag along with a Heavy because of their high defense and Mini-Gun. They can protect you while you cower away from behind. If you enjoy being the leader, the Heavy is a good choice.
Engineers and Spies don't like Heavies because of their Mini-Gun. When your opponents spot Sentry Guns, they usually send out a Medic and Heavy to take them out. The Mini-Gun is weak in long range, but in close combat, opponents won't be able to counter its speed and deadly bullets.
Spies will lick their chops when they spot a Heavy. But no worries, the Heavy can just spin himself around while firing his Mini-Gun to check for any enemy Spies nearby.
Heavies are great on the front lines, but they are also strong ambushers with the Min-Gun, where they can hide in corners and fire at full speed without worrying about reloading.

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