Beautiful. Thematically whole, and impressively polished; truly deserving of a gmtk shoutout.
But it felt more like an art experience than a game, as skill only lengthened survival time, but didn't heighten the experience.
From here, I hope you deepen the mechanics*; because, frankly, there's a feeling of hopelessness, or inevitability, to the game, which fatigues players and dampens the desire to replay it. But just a small increase to player options (through game mechanics), will increase that hard to quantify feeling of hope, of agency, within the player; because players need hope to keep playing and endless game.
*examples: tile power ups like bombs or time slow, or a tile currency system which clears the board after 100 kills
Thanks for your time!