Herne the Hunter

Background
The being that came to be known as Herne the Hunter was an ordinary man, who lived in Britain many thousands of years ago. In fact, he was one of Britain's first human inhabitants. Upon his death, he became an Elemental being. That happens when the spirit, instead of moving on, merges with one of the elements, hence the term.

Herne kept watch over his native land as the centuries passed. This inspired all the subsequent legends of Herne that would written over the centuries.

Herne helps the Wizards
In the 8th Century, the Wizards, fearing that the Source was about to wage war on them, left the Underworld and settled on a Plateau in South America. Herne helped aid them and, as a reward, the Wizards gave him the Golden Scroll. They told him to give it to the Worthy One, when the time was right.

Herne makes contact with Rex Buckland
In 2009, Herne realized that Rex Buckland was the Worthy One, and reached out to him in Rex's dreams. Rex, accompanied by Hannah Webster and Paige Matthews, journeyed to Britain to find some answers. Once there, Rex encountered Herne and was given the Golden Scroll. Herne explained that Rex was the Worthy One (because he was a child of Britain and a former Warlock that has turned good) and promised that the Golden Scroll would bring Rex great knowledge. Herne then vanished before Rex could question him further, so he was left to try and translate the Golden Scroll on his own.

As to whether Herne will ever return, only time will tell.