I'm looking to rig an asset that requires that it be "sliced" or "cut" during gameplay. An example would be a plant that you could cut at various points on the stem.

The bones are being animated proceedurally by the game, with a "stem" image undergoing mesh deformation to align it to the bones. On cut, the two halfs of the skeleton will be moved seperately under unity physics. I'm looking to split the stem image at the cut point (we can do this manually by adding "cut" versions of the stem image representing each cut point and swapping them in on cut).

Does anyone have any advice on how to approach rigging for such a requirement?

Hello! It seems to me like you already have some good ideas on how to rig this particular setup.
If you have two separate images where the one below is already the cut version, and the one on top covers the cut making it look like a unified stem (for example by placing overlapping vertices on both images with the same weights in the portion where one image covers the other) then you should be good to go!
I'd love to give more precise advice should you choose to post some example images of the style of your assets and/or of your animations.

Hi, sorry for my late reply, for some reason i am not getting notifications to my question (i assume its a forum setting i have wrong somewhere).

Thanks you for your help, it's good to know that this approach isn't insane. The slight problem we have with this approach is that it requires our animator to prepare mutliple cuts all along the stem, which gets difficult for longer stems and isn't easy to generalise. I guess what I'd like is to be able to approach this procedurally. Either way it's working alright now, I just worry it won't scale well.

depending on your setup, you might be able to use transform constraints to get what you're after.

It might not be applicable to your setup, but I've created an example with three stem parts. Each part uses an image that can be tiled. The three parts are kept together using two transform constraints. When the stem is sliced, the transform constraint Mix values are set to 0. You can see it in action in Animate mode.

The setup is pretty self explanatory, but please let me know if you are unsure about anything.

This is really cool, thanks very much. I'll drop back in here to report back on how it goes.