It definitely shows its age at a lot of points with things such as level and enemy designs that create a lot of scenarios where avoiding damage is impossible, implied mechanics that may or may not function (I'm pretty sure levelling up in this game does absolutely NOTHING, and there is an amulet that is said to permanently raise your attack stat when in reality it lowers it), and your typical late-game grind padding near the end. Despite all those lows, I still felt like the game was overall solid. It's forgiving enough to keep the dated bits from being too frustrating. Honestly compared to other games of its vintage even the jank isn't that janky all things considered. It's still absolutely a guide game, jesus christ don't try to play this blind. Gameplay-wise it's kinda like a more linearly structured monster world game, as there are a lot of optional side areas and the action-RPG-y stat/money/equipment grind but the actual structure of the levels is pretty linear and doesn't really encourage backtracking all too much (with the exception of shop shit, make sure to buy them damn keys and upgrades when you can.) Maybe it's just been a while since I've been owned by an NES game and it was fun to just get absolutely destroyed by one again, idk. It's definitely a bit of a cult classic in the NES library and I can def see why.