Escapism: writing upgrade/device moves, which included writing the Catapult, one of my favorite devices in Threadbare:
Catapult
Recipe: 3 Helpers, 2 Stuff, and 3 Things that can form the base, arm, and bucket. When complete, the Catapult has two stats: Velocity and Accuracy. Assign a +1 to one of these, and a 0 to the other.
When you use the catapult to throw a payload to land safely on a target, roll +Accuracy. On a 10+, the payload lands directly on the target with no consequences. On a 7-9, the payload lands off-target; this may cause a complication if the target was small, surrounded by hostile forces, or high up!
When you use the catapult to throw a payload to knock something down, roll+Velocity. On 10+, the payload hits with enough force to knock the target down. On a 7-9, choose one:
• The payload hits the target but doesn’t knock it down.
• The payload hits something else and knocks that down (the GM will offer some alternate targets, and you pick which).
• The payload safely and harmlessly lands beyond the target.