Daimonin is an open-source, 2D, isometric MMORPG. Here is the project page at sourceforge - http://sourceforge.net/projects/daimonin/files/Experimental/.
You can try the game on a free public server at the official website or download the client and the server and run them.
Daimonin offers vast world with many quests, races and genders. The game features large number of quests.
You can download map editor and create your own maps.
Screenshots
