Doblons.io

This is a rather well made online game, where you play against other players from the whole world. All you need to do is to put in your name and start playing. You are controlling the game with your mouse. The ship youre commanding can be upgraded. You of course need money for the needed improvements and this money can be acquired through slaying your enemies. Make sure not to let anyone else kill you though, since you won't be able to proceed in the game after that happens. You can create your own game and invite all your friends.