The main mechanics here work really well together! I like how unweildly you become eventually, making it tricky to navigate, those grey blocks especially are a great idea to impede movement! I got a 4x4 but I don't think the game recognized it, which is unfrtunate but I still got the idea of the game and really liked it! My game also includes some of the tetris pieces as mechanics, so I applaud you for implementing moving them like this, it can be deceptively difficult, really great work!