You can see how much you can scale at the bottom of the screens, and the bar next to fills a bit with every new shape, when it's full you gain another "scale".
In the beginning it's not needed to scale all the time, but at the higher levels it is crucial to carefully think about which blocks to scale and which not
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holy, sorry I didn’t realize the comment sounded so harsh, must have been 3 am for me when I wrote it lol. MHM I love the concept and it really gets complicated as it’s not the normal tetris I am used to, A lot of weird shapes come from those big Tetris blocks which makes it challenging, good job <3