Castlevania for NES is an amazing example of withholding information from the player and the player benefiting from it.
In the most basic way, it is a linear game where you get from point A to point B. In its era, this was the majority of games, but the greats managed to use the one formula and enhance it strategically. Mario enriches the experience by providing detours and shortcuts with pipes, beanstalks and power ups. Mega Man designs progressing labyrinths that teach and challenge the player at the same time, building up to a boss battle which tests the player's reflexes and skill.
Castlevania is also that same formula of game. However, it sets itself apart with your main weapon, and sub weapons, which are inherently interesting and fun to use. Castlevania's wall chicken is incredibly famous because it spawned a significant "aha!" Moment in video game history. How it does this is through enemy placement and the environments it provides, with bats and medusa heads who come at you at different angles, the player will often be met with instances where they attack through a wall.
This teaches that you can kill enemies in or past walls with your whip, and in the rare case, it reveals that walls can have hidden items. This discovery introduces an exploration idea that the player didn't think about before, but now that they know chicken is spread throughout the game, it incentivizes exploration in what is a linear game. It is still a basic point A to point B game, but it is no longer just that to the player.