This is kills with any form of weapon. Sniper Kills, Grenade Kills, Pistol Kills, and Knife Kills.
How to boost kills:
The best way to boost this is with at least four players that will stick with you through the entire process. Choose who will be hosting the games in what order. The person who is host will host two matches with a max of 50 kills. Each time the person hosting will host two games. The person who is host is the one getting the kills, not the other on his teammate. So each time it rotates hosts. You will accumulate a total of 100 kills each time. Then they will rotate to the next player and start again. You can add more players to have the kills go faster.
How to boost wins:
You will need a minimum of four players and to play on the level Canyon in a Ranked Team Deathmatch game, so choose only one person to host the game. Set the game up with a maximum of 5 kills and four players to start, then have the same two people join in after him while the 4th person waits for them to be in the lobby. The two people who join will be on the opposite team of the host, and the fourth player will be on the host's team. Have the team that is losing to run to the bridge while the team winning will just kill the losing team. Continue this while switching who wins each round. Red team wins a round, and than Blue team wins the next. Make sure to have the same person host every time, and once you get the pattern down, you can finish each game in around a minute.