Slither.io

Slither.io is a neat arcade game that has been around for some time now but has barely made it to the Microsoft store. This game is based on the ever-popular mobile game snake, only that it has an online twist to it.

The game doesn't have an actual goal. Instead, you have to grow as much as possible before your ultimate death which is pretty much inevitable.

You start by selecting a nickname and a color for your starting worm, and then you start munching on sparkly marbles of light that will make you grow with time.  You move controlled by a mouse, and you can also boost your speed, but this will reduce your ability to steer left or right. Unlike the mobile version of snake, you can overlap with yourself as much as you want, but you aren't allowed to hit other worms in the side or else you'll die.

Killing another worm will make all the light that it had gathered to be released in proximity, and thus very easy to eat by others, and that is where the competitive nature of the game comes from, as the fastest way to grow is killing other worms of similar size as you, and maybe even bigger, if you're lucky.