As its name implies, this version of the game revisits the classic Castlevania II: Simon Quest which first appeared on the Nintendo Entertainment System. Graphically, they've cleaned the game up quite a bit to look like a 16-bit game, and they've added tons of other new features, like a save function and a better menu system.
The game itself boasts many improvements on its original version. Jumping, for example, is much more fluid and precise; even the combat system is more exact and enjoyable. There is also a good variety of enemies that have been recreated, which really gives a boost to combat, compared to earlier titles.
Castlevania II: Simon Quest Revamped is an excellent representation of the Castlevania franchise. Not only is it considerably better than the original, but it provides an excellent game for fans of the 'metroidvania' genre who don't have many options available for PC.