One of the few fully-3D .io games, Warbot.io is surprisingly detailed, and it features a level of depth not typically found in games of this sort. There are various bot types and upgrades for each bot, allowing for a diverse set of playstyles.

Complex enough to warrant a tutorial, this may not be the best choice for newcomers to .io games. However, for those looking to graduate from other overly simple browser games, Warbot.io is a great option.