Re artificial earths. They were common pre ban. They were put in to encourage foxes to the more poorly foxed parts of a hunt country.
A farmer might happily watch a family of young cubs who'd been born in an artificial earth that he'd put in playing on his land all summer, and ensure that they were safe. Then he'd tip the wink to the huntsman come the cubbing season in autumn, who would send hounds in. The field would be positioned around the outside of the covert 'holding up', ie making lots of noise when the (now virtually fully grown) cubs tried to escape, and the young entry of hounds would learn their trade by killing most of the cubs near their birthplace.
As far as I know the creation of an artificial earth with the intention of encouraging foxes is still not illegal, though cubbing as described above has been banned since the Hunting Act came in.
One does wonder what the 'official' reason was for the relatively recent refurbishment of the artificial earth in E.Essex country, though 🤔. Clearly not so that a sicko with a fork could harvest and torture foxes.