I would love to see steam achievements for this game

Thanks for making this game. It's a lot of fun and it's really simple to play and me and my friends like it a lot

The sound goes up after every new Level, even though I lowered it to 10%. And even If I die it goes back up.

There's this bullet point at the bottom of the store page: "-Can you find the secret mode after completing the game?" I like to try and 100% complete the games that I play, but even knowing about this while playing the game, after I beat all the levels, I'm really not sure what else there is to do. There weren't any obvious places to me to look for any side content. Does anyone know what the secret mode being referred to here is and how to find it (assuming such a thing exists at all)?...