General What is the most overpowered unit you’ve ever used?

[blitzmaster_84]

I don't like the unit that spoils the balance of the game. I remember the RTS I played that time, there was a heavy tank and once you have 5 of them, the game is over already. All the enemies would run for cover. Since that day, I don't trust “overpowered” units anymore. They will make the games very boring.