It’s handy to know, so here they are:
https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts https://mirror1.malwaredomains.com/files/justdomains http://sysctl.org/cameleon/hosts https://s3.amazonaws.com/lists.disconnect.me/simple_tracking.txt https://s3.amazonaws.com/lists.disconnect.me/simple_ad.txt https://hosts-file.net/ad_servers.txt
To restore Pi-hole to the default blocking lists, just delete all the lists but these six lists.
Note: There used to be a seventh list, which has been discontinued, so you can safely delete it:
If you visit that page in your web browser, you will simply get the message:
# ZeuS Tracker has been discontinued on Jul 8th, 2019
So, go right ahead and remove it from the lists to clean up your Pi-hole!
To delete lists, simply go to the web interface and sign in as admin, then Settings > Blocklists and use the trash icon next to the lists you want to delete and then hit “Save and Update”.
Alternatively, sign in to your Pi-hole using SSH and edit
/etc/pihole/adlists.list with nano or your favourite editor, and then update the lists with