Press play to watch the example. Pause before editing; reset returns every marble and weight to its starting position.
Choose a part from the drawer, then click an empty peg. Click a placed part to select it and click an empty peg to move it. Rotate with R or the Rotate button. Delete removes a selected part. Arrow keys move the highlighted peg; Enter places or selects.
Gears transmit power through neighboring gears. A powered lift releases a marble along its arrow. Tracks guide it one peg at a time. A paddle releases an adjacent weight, which pulls an adjacent bird into a bow. Each lift releases once per run.
The motor and bird are fixed. Everything else is yours to rearrange. Empty pegs stop marbles, so connect the entire route. Use Save to keep your invention in this browser.