Cool idea! I like the different kinds of blocks, spwaners and repulsers are both good. There's a bunch of stuff you could do with that if you took it forward. The random blocks add a good amount of challenge, but it could be good to have some cost associated with placing a block or have higher cooldowns after better blocks. As it is, I beat hard by just putting a couple of block spawners on the back few rows and then just spamming blocks in front of them whenever they were off cooldown. Very much enjoyed it though, nicely done!