Tango-Tiger

Eat thousands of small snakes to make you a giant snake with incredible length.
Colorful mutated snakes in slitherio

Slither.io is an awesome io game released in 2016. Control a snake, eat glowing orbs to increase your snake's size. Your main objective is to become the longest worm in the arena and defeat all players. If your snake's head collides into any part of another snake, you will explode and the game is over.
When a worm dies, its body will turn into shining pellets (orbs) that it had before its death. Players can consume pellets dropped from dead worms to grow their size. These pellets give more mass than normal pellets.