okay so

when an object in minetest gets its hp set to zero, the corresponding on_death method gets called (this method is defined by whoever defined the object)

AFTER that, the object is destroyed. which makes sense, because destroying it before that would render the on_death method incapable of doing anything like e.g getting the object's position

HOWEVER; the object's children (in minetest's attachment system) are all detached before the on_death method gets called, so calling self.object:get_children() in the on_death method always returns an empty table and you can't do smth like e.g. rescaling all the object's (now ex)children via the on_death method.

which is luckily smth that one can work around relatively easily by not using minetest's build-in damage system for the object or by overwriting the object's on_punch method and by also making sure that nothing ever called set_hp directly, but uuh. it's still annoying and weird. and unmentioned in the documentation.