Zeach (Matheus Valadares) was the original developer of Agar.io. Valadares is Brazilian. He is a biologist. He initiated the development of Agar.io after he had created a game called Voar.io. Later he sold Agar.io to Miniclip, who previously had developed the mobile app for the game. Apparently he kept working on Agar.io for a while, helping Miniclip to maintain it. However, eventually he moved on and created new games.