I know it's been a while but I have been holed up in my house for over a week now so I thought I'd post my latest project. I have posted similar items before, but nothing on this scale. It is a hybrid device that uses both bow arms and surgical tubing to get maximum velocity over a relatively short draw. Even so, this is one of the largest devices I have built, 20" draw length and 30" total length. You can see the many pieces it was assembled from here, I have to work within the size restrictions of my printer and the build plate (250mm x 210mm x 200mm).
No idea what to call this device, I think the technical term might be a sling-crossbow as it combines features of both (unlike a sling-bow it has a trigger and a locking mechanism so it can be loaded and then held at the ready without effort).
The original device that inspired it:
A small toy crossbow that the kids enjoy, used to play a re-creation of an old board game from the 80's where you built and destroyed castles using medieval siege equipment such as ballistas, catapults, etc. In this video you can see it destroying a wall made from loosely fitting 3D printed blocks.