You can also use Preview to carve up PDFs and assemble new documents from the pages of multiple other PDFs. This is really handy for making e.g. custom bestiari

You can also use Preview to carve up PDFs and assemble new documents from the pages of multiple other PDFs. This is really handy for making e.g. custom bestiaries for RPGs, using pages from official books, since usually you use only a few beasts in a campaign, out of a set of potentially hundreds of first- and third-party ready-to-use beasts. Nice to have them all in one PDF, with nothing you don't need. And of course you can pdf-export whatever you like from your own documents and mix that in, too. For some reason I've never bothered to figure out, I do sometimes have to copy a PDF before it'll let me re-arrange or copy/cut individual pages out of it. But not always. I assume it's because of some kind of flag on downloaded files in macOS, but IDK.