Very few website owners are familiar with the built-in comment blacklist WordPress has. Default WordPress comment black list is located in your admin area dashboard Settings -> Discussion page. It accepts values (words) to identify spam on incoming comments.
You can either update this blacklist manually, or make use of a detailed global comment blacklist which is updated on regular basis.
Here comes the use of Blacklist Updater, a free WordPress plugin that connects your website’s commenting system to a global blacklist on GitHub.
Don’t worry about the consumption of your hosting resources. The plugin is very light weight, it checks the global comment blacklist multiple times a day but run updates only when any new anti-spam values are added to the global blacklist on GitHub.
To start using it on your WordPress site, all you gotta do is install and activate it. That’s it, you are done. There are no settings to configure.