An old-school trick involves using Google Translate as a proxy.

If one URL is blocked, try adding "1" to the end (e.g., diep-unblocked1.com ).

Today, the hysteria around Diep.io has settled, but the game remains a titan of the genre. It represents a specific era of internet culture—a time when browser games ruled the roost and Flash had just died, leaving a void filled by the simplicity of the .io domain.