Glad you enjoyed yourself. Yes, shooting up and down was not properly introduced, my bad, only the level design hints at it. Now I wonder how long it took people to realized that.
"Heretics" sounds like an overstatement; if so, I would have never added the option to use WASD xd; however, I forgot to add other options for the shooting and gravity buttons. I mainly tested the game with a gamepad. People around me don't really play FPS or computer games that much, I did not realize WASD was a standard untill some years ago, and because I didn't have an issue with Arrow keys, I figured people would not have an issue adjusting to it, I was wrong, muscle memory, habits, are too powerful. Also, I didn't know people had issues with their arrow keys like you, sorry.
And about the NES graphics, well, I didn't have enough time 🤣. I know my game sucks in terms of graphics, and no music, only sound effects. I focused on the gameplay and level design a lot, even making other people play me game to find bugs and parts of the design they didn't like. Anyway, thanks for the comment.