Konami was in the habit of ruining the difficulty of their games overseas so they couldn't be beaten in one rental back in the day, so the American version of the third Castlevania is pretty miserable. The Japanese version, on the other hand, is one of the better platformers on the console, in addition to having much better music. It's mostly held back by the NES standard of losing significant progress after a few deaths, and that really becomes a problem in the later stages. The underground route also has some bullshit in it, especially if you didn't take Alucard with you. But the levels, enemies, and the abilities of the playable characters and how they play off each other all feel more thoughtfully designed than what you see in most non-Nintendo games on the console.