Thank you for playing! I'm so excited you liked it. At first I went with full random approach where number on dice roll were number of blocks. But the irregular shapes destroyed any attempts to balance the difficulty. So new approach was to keep roll = number of block but hard code the shapes. Mirrored (like 2-5, 5-2) roll also creates mirrored shape. Last change was to double rolls like 1-1. Those give you smaller pieces to fill the holes.