External Dynamic Lists for Rules
I have seen a few others on reddit and other public forums discussing this. I come from Palo Alto firewalls and I'm used to building policies for somethings using an EDL (External Dynamic List).
One primary use case for this is to specifically deny Tor exit nodes for all my inbound policies and including the block sites list. Which I can copy the Tor feed, but it updates and is dynamic. There is also many other EDL lists uses cases for hooking into for various kind of feeds. I do already have it set to temporarily block unhandled packets and that is good. But I want it where my webservers/ftp etc is blocked from these nodes as our business doesn't require any Tor based traffic.
Some examples of of what you can do -