Paper.io

Paper.io is a popular Splix.io-like game developed in 2018 by Voodoo. A sequel, Paper.io 2, is hosted on the same website. Paper.io 2 was released in 2019 following great popularity. A slightly different game but visually similar to Paper.io 2, Paperio.live, is also popular.

Paper.io
In the game, the player has to compete with other players to capture the entire arena. Players may defeat others by running their head into other tails; running into their own will kill them. The point of the game is to capture as much territory as possible by encircling it. With enough gameplay, skins may be unlocked, which enhance the experience. There are 8 gamemodes in Paper.io: Classic, Small, Fast, Turbo, Small+Fast, Slow, and Inverted Controls. There are also quest challenges which unlock skins.

Paper.io 2
In the sequel, gameplay is similar, except the player is guided by the mouse rather than the arrow keys. There are 4 gamemodes: Classic, Small, Fast, and World Conflict. World Conflict is unique in that the spawn dot is where the capital of the chosen country is, and all that is needed to be defeated is to have the capital become captured by another player. Unlike in Paper.io, the border does not kill players unless they run straight into it or accidentally backtrack into their own line if they are hugging the edge.

Labyrinth
Labyrinth has two gamemodes: Classic and Egypt. Labyrinth is a singeplayer maze adventure, where the player must try to escape without running into the walls.

Agarpaper
Agarpaper is a spinoff of Agar.io, but using squares rather than circles. Gameplay is similar to Agar.io.

Minigames
There are also minigames. Paper vs Blocks is a minigame where the player has to accumulate score by eating the circles while steering clear of the squares, which can kill the player. Christmas is a Christmas-themed minigame where players must avoid running into the presents, which kill them. Otherwise, Christmas is played just like Paper.io.

Skins
There are a number of skins that may be unlocked by sharing, completing quests, or merely by regular gameplay.

Paperio.live
Paperio.live is a small Paper.io clone with many similarities of gameplay to both Paper.io and Paper.io 2. There are 6 servers, three on the US East Coast and three on the US West Coast.