part 2! This one is super cool. Basically, each of the polygon lists contains all of the vertices of each polygon (in the pattern x y x y x y for as long as it has vertices) and then the "Firefly's Polygon Intersection Algorithm" block returns whether they collide or not in the first value of the "polygoncollide" list (ignore the other numbers in there.) I'm going to do cool things with this. This system can be used for perfect mathematical collision detection, offscreen included! please give credit