The game's concept is interesting. You have to build a bunch of blocks within a set time limit to protect your crystal from enemies. Not bad for your first jam submission and your first game you've made on itch.io. I suggest that you give the player lots of money before each of the waves so that the player can use them to buy a bunch of materials to defend their crystal from the enemies. By the time I got to the 2nd wave, I only survived for 20 seconds before an enemy with a bandana on its head reached it.