Cogtrail

Cogtrail is a programming puzzle game. Build a program from command blocks (forward, turn, jump, pick up, place, a loop, a function and an if-gear-ahead test), press Run and watch a little robot carry it out step by step, with the running block highlighted. 30 workshop levels introduce one idea at a time: sequences, then jumps between heights, then loops, functions and finally conditions. Each level gives up to three stars for using as few blocks as its reference solution, and every level is checked solvable. It plays in the browser with a keyboard, mouse or touch.