Gamemodes ae a thing in Kugeln.io to choose or know what is happening there are 3 of them.
Death Match is a gamemode where you fight and everyone is your enemy unless you are teaming. This mode can be played in all maps.
Team Death Match
Team Death Match or TDM is a gamemode like Death Match except you get help by other people and in teams. There are 2 teams and all maps are payable with this.
Capture the Flag
Capture the Flag is different to the other two. You do not need to kill the most to win, you need to go to their base and get their flag and bring it to your base without the flag being taken. This gamemode is also combined with the desert map can give you a lot of XP.