These will have 2 or 3 parts, with a bat, the back cover and an insert (to be printed in clear or possibly glow PLA). The insert may be optional but I need to see how it looks without the insert to know for sure. The larger version will require some M3x6mm screws (yeah it's a weird size but an M3x10 may work if a nut is added as a spacer. As always, I will post this up to Thingiverse when it is ready, and I'm putting a rush on this since Halloween is right around the corner.
Update 10/18/2021: I think I have the designs finalized and have printed a couple of tests, but I still need to re-print everything to verify things work, so I will end up with a couple extra bats. My test print of the ghost failed about 80% through since I had to use ABS and it popped off the bed (it was the only type I had in clear), but I got enough printed to confirm it will work and looks really cool with the LED inside. I will reprint it with a brim next time. The models should print with minimal supports, though obviously the Jack-o-Lantern will need some, it should not matter how ugly it looks inside (real Jack-O-Lanterns are stringy inside anyway :D). I expect it will be the end of the week before these are tested and then I will post them up.
These will need Black, Orange and Clear filaments (or they could be painted). Clear is a requirement however since the LED's need to be able to show through the material.
The pic below was a test of the smaller bat, the larger one will be 1.5x as large and I have made a few changes to the design as well (but the changes won't affect the overall appearance).