While picking u p K slashcards, one of the "CardHolders" spawned outside the playable area. I believe it was "ko." I was able to use a special to do half damage, but then he moved out of range. Eventually, he just died. I couldn't find the card after that. The level let me exit with only 4/5 cards. I could not reproduce this.

This is really great! So far the best way to immerse an alphabet translation I've seen. Great graphic style, and fun music.

The English keyboard is really difficult to work. Perhaps you might organize it in a fashion similar to the Hiragana KB, with consonants on the left stick and vowels on the right. You might have to include a vowel "consonant" for that to work. 

I had to get my Xbox controller to play this game. The KB layout frustrated me when I had to use the "right stick". Maybe it would have been better if the arrow keys were your right stick.

There are no health pickups after the first few minutes of the game. 

Finally, I found myself very sad when I couldn't enter the N level; meaning, I wanted to continue playing!

I'm looking forward to your finished product!