You can read about how Call of Duty: Black Ops II changes multiplayer class-selection with the introduction of a pick-10 system. It’s all explained right here. Or you can just stare at this board game prototype of the system from the creators of the game.
https://lastchance.cc/black-ops-ii-multiplayer-blowout-scorestreaks-replace-5934476%3C/a%3E%3C/p%3E