Which is really ironic, as my late father is the formal registered inventor of the Folding Crossbow.
https://patents.google.com/patent/US4926834A/en
No, this one isn’t a folding crossbow, but it does seem powerful enough to potentially be deadly. It’s raining today so I’ll have to wait for a good weather day and find an old used slab of wood for target practice.
I have one just like that and the strings will break and eventually the bow arms will bend, but you can use it for quite a long time. They are a lot of fun.