eee.io
Eee.io (Excellent Enigmatic Explorers) is a popular web browser game about controlling a circle throughout a large abstract map in order to find random items. The player receives points throughout the game for collecting each item, which adds up to a final score upon death.
At the start of the game, the player is given a list (called the Crazy Collector's Checklist in-game), which provides hints pointing towards a random group of specific items. Each item has a different rarity and class. A run ends when the player dies, either from another player (through PvP combat) or from their environment. Every item has its own base score, with higher rarities generally giving higher score. In addition to this, items listed on the player's CCC grant higher score (though it is still possible and valuable to collect items not listed,) items of the same class boost each others' score, and many items have special effects which change score in many different ways.
The game holds many similarities to Agar.io, with the map and all items being represented as abstract polygons and all players being coloured circles, and could be considered part of the ".io genre."
Despite not receiving any updates for several years, the game is still relatively popular, with an active fanbase both in-game and on various social media platforms. Its multiplayer setting and extremely random nature, along with a high skill ceiling, allows for a good degree of replayability.
The game is also host to an urban legend: the NPC, an item which is supposedly very valuable but has never been found. For more information, go to eee.io/npc.