This is another myth I was unaware of so that's nice. I knew that numerous Russian principalities became subject to and eventually broke away from the Golden Horde, but I've never heard of this particular story. I like that you included an explanation of the character and the background of the myth to provide context.
The game itself is surprisingly difficult, it was hard to when an enemy was in range, and the fact that misses seem to also damage you somehow don't help with the difficulty. I think it would've been better to have only one enemy at a time come at the player at the start, and have it ramp up from there.
The visuals for the warriors was quite nice and the animation seemed to have a fair bit of effort put into them. But sadly I didn't see them for more than a few seconds.
You did good, the game just needed more time for balancing I think.