Akin to Mario 2 and Zelda 2, Castlevania 2 was born of a time where these franchises were not yet fully committed to their mechanics and/or aesthetics. The results in all 3 cases were amazing and stand as a testament to this brief but glorious process of how these franchises evolved from the primordial ooze of the post-atari consumer wasteland.

If you know how great this game is, you know, and you probably had a lot of help from Nintendo Power, etc... but it could have been so more popular and reflected upon with more respect if it had a proper translation. Regardless, its blueprint is akin to Metroid; the first step Castlevania would take with the mechanics that would become the core of Symphony of the Night, Circle of the Moon and onward. It's an open map, you can go anywhere that you want to; there are multiple routes to get to certain locations. However, you need certain items to access certain locations. There is XP, and currency. Acquire weapons using currency to upgrade your attack power and purchase consumables. All of the basic elements were here in 1988.

Needing certain items to access certain locations and acquire certain items is really where the bulk of the confusion comes in with this game. The townspeople straight up lie. There is no fire on the sixth tree in Denis Woods, and there is no crooked merchant in the first town. The proper translation in that case would have been "merchants have to deal in hiding". That's why merchants are always in basements and behind false walls that have to be broken with holy water. Dracula has eyes everywhere and nobody wants to get caught assisting you.