What is agar.io xyz?

There is no specific information about agar.io xyz, as "xyz" does not appear to be a part of the official agar.io website or game. It is possible that "xyz" is a reference to a private server or a modification of the original game with custom features and rules. However, it is important to note that using unofficial or modified versions of online games can be risky and may result in security issues or account bans. It is recommended to play the official version of agar.io on reputable websites or platforms.