I don't know "one of the best downloadable games ever," but I just finished Chapter 1 of the demo. Visuals are great, much better than I figured they would be, and the combat is pretty good, too. It's sort of what I imagine DMC might be like in 2D. It has major Castlevania vibes in the setting, but it's more old school Castlevania instead of Metroidvania -- there are individual levels (point A->B) instead of one sprawling castle.
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peace comes from within