Chivalry 2

There are many other achievements that require wins all throughout this game so this will come along the way but Mason team is the Red team (of only two different teams). All you have to do is win 10 times as this team. A couple of ways to boost this are as follows

1) When you see a team is close to winning and you aren't on it you can press and then go down and press on change teams and then choose the team you wish to join. If there are spaces open it will change your team for you. Spaces tend to open up more often in the 64 player mixed modes.

2) As of 6/09/2020 all of the win-based achievements count each win as 2 wins.

You will get this just from playing the game. The game has two teams. Red and Blue. The Mason are the reds. Play a team based game and just complete the objectives and claim victory 10 times as the Red Masons to achieve this.