The UK National Cyber Security Centre (NCSC) release weekly IOCs of malicious domains. These are freely available to download as a CSV direct from the NCSC CISP portal. This feature request is for DNSFilter to automatically add these IOC domains from the NCSC to your data sources. At the moment, I'm manually importing these domain to the block list. Note that I've checked some of these IOC domains with your domain lookup tool and several are not categorised as being malicious. This means they are being let through by your service which is not the desired behaviour.