As of 2024, Real Madrid had played more UEFA Champions League games than any other club, with a total of 476. Meanwhile, Bayern Munich ranked in second place, with a total of 382 games played.
Call of Duty Warzone is a free to play game. It's not on GamePass and it doesn't need Xbox Live Gold either. MW2 and its multiplayer component is not free. You need to buy it if you want to play the single player game or MW2 multiplayer.
