How to play
- Everyone builds 3 marble machines together. You get one 8×5 section and build it blind: nobody sees anyone else’s section until the run.
- The ball comes in through the green opening on the left and must leave through the yellow window on the right. Your exit is the next section’s entrance.
- You get 6 random pieces plus 3 ramps (gentle, steep or flat) and can place up to 8: springs, fans, conveyors, tubes, buckets, seesaws, bells and more. Test with the by-the-book ball as often as you like.
- During the run everyone watches the ball go from section to section. The real ball may arrive differently than the test ball. If it falls or gets stuck, Grandma’s hand puts a fresh ball in the next section.
- Points: +3 if it leaves through your window, +2 "Sturdy" if you got a wild ball and it still made it, +1 per bonus piece triggered (max 3) and +1 for you and whoever passed it to you if it arrived without Grandma. If the ball crosses the whole machine unaided: +5 for everyone!
- Last place picks an extra golden piece for the next machine. With 2 or 3 players each person builds 2 sections. The match ends with funny awards (+2 each) and a card to share.
Big Contraption is a creative party game for 2 to 16 friends on their phones: everyone blindly builds one section of a giant marble machine with ramps, springs, tubes, buckets and a sleeping cat, then you all watch the run together. Will the ball make it to the end, or will Grandma have to help? Real physics, big laughs, no downloads, no sign-up.
