SPRITE BASED A STAR!! Press 0 to reset the course, and press D to add a "blocks" coordinate. You cannot erase any blocks, though.. Please make the course closed!!! Because A star involves checking every single pixel inside, the course needs to be closed otherwise the searching clones will wander forever!!!
I implemented the algorithm explained in Sebastian Lague's youtube video on pathfinding. https://www.youtube.com/watch?v=-L-WgKMFuhE the link. Very laggy, by the way... The reason? This sprite based method uses clones, and because Scratch's clone limit is insanely small, this project has a pretty good chance of crashing.