Have the ISP place their gateway/router into bridge mode. This will pass the public WAN IP directly to your router, allowing it to handle NAT, firewall policies, and port forwarding without double NAT.

I’ve been hosting public-facing servers for several years and regularly run dedicated servers for my son. I keep the ISP gateway in the setup because they provide a substantial discount for using their modem/router rather than connecting the UDM Pro directly to the fiber ONT.

A wise man once said devs that are afraid of losing their jobs dont go on to make great games. I was going to purchase this game but now ill wait till its on super sale.