uMMORPG is used by a lot of happy developers. Check out their projects!
The multiplayer version of the mobile game hit Blockstory – currently in development with uMMORPG.
Naïca Online [naicaonline.com]
Schools of Magic
Hexa Heroes Online
Waves of Time is one of the most promising upcoming 2D MMORPGs – with a huge community already waiting for it to be released.