Grinny 2D is now a thing 

but just Grinny 2 in a way except 2D

Grinny Update (UPDATE v3): Now Free (I needed to make the servers a VPN), Mac and WebGL is now supported, Is now shipped using Unity 6 (For a while maybe), If you want to host your own WebGL Server, It will be downloadable on the page down below, and now also available for mac (Kinda buggy) 

Online Browser Play (Unblocked Hopefully)

You can play the awful demo version of the game by clicking the Try Demo  link.