@Jens_Rasmussen pixel/analog movement, active battle system, basic 3D, lighting, character customization, all of that is already possible with rpg maker. Relatively easily too. One could definitely make a more old-school mmo with it. There are better ways to go about doing such a thing, but rpg maker is very easy and very well designed, which is why you get a lot of slop from it but also some really notable stuff.
Multiplayer, I imagine, would be even worse.