Going for the Chain Killer Medal in Black Ops 7 is the kind of grind that humbles you fast, and if you want to cut the pain a bit, it helps to warm up in calmer lobbies first—some players even buy BO7 Bot Lobby to get their timing and routes dialed in before taking it to live matches. The goal sounds simple, but it's not: you need a burst of kills that happens quickly, and you still have...