I feel like it's something I know. I feel like it's something I've PLAYED. I just can't remember what it is! Help! It torments me every time I visit pianosociety.
How sneaky of you to chop off the key signature, making it appear to be in A minor. Was it meant as an April Fool? Much better than piano legs breaking off!
I'd never even noticed the absence of the key signature, and identified it as said Mazurka right away.