(Shamir’s scheme is delightfully straightforward, but if polynomial interpolation over finite fields isn’t a thing you feel in your bones, try inventing an n-of-n-shares scheme that only uses xor and a random-number generator. Gb nyy ohg bar bs gur cnegvpvcnagf, tvir n puhax bs enaqbz qngn nf ybat nf gur frperg; gb gur ynfg bar, tvir gur kbe bs gur frperg naq gur enaqbz puhaxf. You probably don’t want that in production, but it’s nice to figure it out and even utterly simple to prove it secure, provided you understand the proof for one-time pads.)

This immediately came to mind as a possible tactic because polynomial interpolation is covered nicely in A Programmer's Introduction To Mathematics[1] which I started reading recently. Highly recommended.

[1]: https://pimbook.org/

Oh yeah, I know about that. I meant to intentionally release only part of the key specifically to make brute-forcing easier for your heirs. I mean, hey, they gotta work for it, you just give them a leg up! :)