I love the concept and would be awesome to see this further developed. I think the idea could easily carry a full game, it's a good bit of fun.
Love the character and vibe of the world here, although the font is difficult to read and would be particularly challenging for anyone who struggles with reading. I'd recommend using this font for menu purposes only, but use a more reader-friendly font for dialogue.
I could be bad at it, but I struggle to get past the first wave consistently. I love the theme this brings (big bad hero, very good at squishing little ones), but I'd love to see the ones I'm not controlling have a touch more survivability. I tend to find them all dead shortly after they appear.