Note: Implementing this requires that you are identifying your visitors to Emercury, and have the tracking code installed. Read about identification first if you haven't yet.
This one is pretty simple and fun to do.
Just create a new automation with the automation builder
In the first screen, choose the option "track event"
You will get a popup where you can define the specific trigger.
Under type choose "Page Visited"
Select the website (you define that in tracking setup)
Select the list
Enter in the url path, for example https://example.com/pricing/
Enter how many times they should visit a page before it triggers this automation
Choose when the count starts.
For example if you put "1" and select "all", the automation will trigger for someone even if they visited the pricing page a month ago. If you select "from now" it will only start counting visits after the automation launches.
That's it, you can build out the rest of the automation as you see fit
You can assign or remove a tag to this subscriber, send them an email, check some more conditions, change, add or remove custom field values, or even move them between lists.