I wonder how many times it has to be said in this topic that Rondo is NOT a difficult game before people get the idea? :P I'd probably go so far as to say it's the easiest pre-SotN Castlevania, even beating out Castlevania IV. If it had traditional controls, it would probably be much harder, but both Richter and Maria are so nimble and swift that you can blow through most everything with ease. Unfortunately, the developers didn't seem to take that in mind much, so they neglected to take the time to build a challenging game around those controls.

Of course, it's still a brilliant game and worth playing even if it doesn't quite provide an adequate challenge. The same can be said of Symphony of the Night.