Team Fortress 2 in the near future to gimp overpowered abilities and boost lesser ones.
One example is the Spy's Dead Ringer, which allows Spy's to avoid death by turning invisible and leave a Spy corpse. The ability blocks 90% of the damage from the activating hit as well as during the first 6.5 seconds of the feign death Cloak, saving them from headshots by Snipers, backstabs from enemy Spies, and Taunt kills.
According to Valve, “We’ve gotten emails from players who describe the item as frustrating to fight against, requiring too little skill from the Spies and too much from their opponents."
In addition, equipping full item sets will no longer reward players with buffs. Rather, the buffs will be individualized. “One of our goals as we continue to work on Team Fortress is to support a wide variety of play styles,” explained Valve. “In order to achieve that, it’s been vitally important that the weapons in the game are fun not just to use, but to play against.”