FlyFF - Flyff (Fly For Fun) is one of the greatest running fantasy based MMOs.
Super Meat Boy - Let's start with what's the same: Dr. Fetus is still a jerk, gameplay is super challenging but fair, there are tight controls and great levels and you will die. a lot.
Wartune - Wartune is an Action-Adventure, Strategy, Massively Multiplayer Online, Role-playing, Fantasy-based and Browser-based video game.
Hollow Knight - Descend into the Dark Venture down into a beautiful, ruined world of insects and heroes
NosTale - NosTale (The Tale of Nomads of Silver Spirit) is a totally free MMORPG that includes simple (but beautiful) graphics and also lots of class options.
SuperTux - SuperTux is a classic 2D jump'n run sidescroller game in a style similar to the original Super...