I like the concept a lot. I will admit, I was frustrated that the controls listed on the page were WASD and space... and then I started seeing H, E, I, A, O in the game. Also, I would recommend starting the player on a lower difficulty and ramping it up after a couple successes. Having 3 enemies with 2-4 letters each, and only mere seconds to try to figure out the sequence was too much. But the concept has a lot of potential and I think it could be a lot of fun with some fine tuning.