You're looking for a ORPG maps which contain a save/load system and dungeon/boss/arena encounters? The first one that came from the top of my head would be
Tales of Athelor. It fits all the criterias you mentioned (save & load system, bosses/arena encounters) and in my opinion, it's quite well made. It is however, dead. Halfway done. But the stuff that has already been done it quite a pleasure to be playing.
If you're looking for pure boss encounters, again from the top of my head, then I'd suggest
Impossible Bosses and
Battle Against Time. Again, in my own
personal opinion, I'd rather much prefer Impossible Bosses over Battle Against Time. Mostly because Impossible Bosses actually requires a strategy to overcome the various bosses and, although it might take some time, sweat and frustration, is a joy to play, and even more so when completed. Battle Against Time is good as well, but more eye candy than gameplay. There is some strategy to it however, but not as in-depth as Impossible Bosses. The spells though are very well made. It is also,
very computer taxing so if you don't have a great computer, I'd suggest lowering the graphics but a notch.
Hope it helps.
PS. Structure your sentence properly. Or at least use capital letters when appropriate.
