House of the Dragonisn’t particularly interested in most of the mystical aspects of its source material.Game of Thronesrarely indulged in its warlocks and incantations, but it was a bit more willing to explore. Aside from the supposed prophecy,House of the Dragonrarely mentions the weird and wonderful aspects of Westerosi lore. Daemon’s experience in Harrenhal was a unique example of the show tangling with strange lore. Just before Daemon watches aGame of Throneshighlight reel, he sees a bizarre figure with a prominent pair of antlers in the godswood.

House of the Dragonis a prequel set 100 yearsbeforeGame of Thrones. Though the two shows are closely connected, the showrunners have managed to avoid shoving in too many callbacks and notable references. The fact that the characters are the distant relatives of the icons fans came to know and love a decade ago never leaves focus, but it’s a background detail. Daemon’s bizarre final hallucination in Harrenhal’s godswood is the most explicitGame of Thronesreference so far.

One of the Children of the Forest talking to Bran in the Three-Eyed Raven’s cave in season 6

What are the Green Men?

That tall fellow with the antlers is a member of a group called the Green Men. The Green Men are mysterious figures who sprouted up inthe Dawn Age. When the original human settlers crossed the land bridge from Essos into Westeros, they encountered a few indigenous humanoid species. The small Children of the Forest and the massive giants hated the way the First Men treated their natural environment. When humanity burned a field of heart trees, sacred weirwood trees with carved faces that the Children worshiped as gods, they sparked a war with the locals. The First Men and the Children of the Forest fought for thousands of years. While the humans were physically superior to the Children of the Forest and technologically beyond the giants, the locals had access to mystical powers that allowed them to fend off their invaders. They could commune with beasts,see the future, and even command the ocean like a weapon. After generations of needless bloodshed, the wiser voices in both groups prevailed. Finally, the war came to an end with a legendary pact.

Humans and Children of the Forest met to sign the peace treaty on the Isle of Faces in the lake known as the God’s Eye.The indigenous species, who were much smaller in number than the human invaders, gave up most of Westeros. They agreed to live in the deep forest, allowing the First Men to control everything else. The First Men agreed to leave the trees alone, sparing the indigenous species' most sacred treasures. To seal the deal, they carved a face into every tree on the Isle of Faces, turning it into a sacred place. Humanity agreed to appoint an order called the Green Men to protect the Isle of Faces. When the Andals later invaded, wiping out most of the remaining indigenous species, they found the Green Men too strong to overcome. They’re said topossess great magical powers, possibly learned from the locals. They may even harbor some surviving Children on the island. Some believe they have green skin and antlers, but others maintain that they simply wear headdresses and cloaks. They guard the heart trees with their lives.

Addam speaking with Rhaenyra Targaryen in House of the Dragon

Why does one appear to Daemon Targaryen?

Daemon Targaryen spends mostofHouse of the Dragonseason two hallucinating at Harrenhal. He’s at the cursed castle in the Riverlands to call up an army. He fails at it for a long time, but a teenager pulls him out of the fire and saves his attempt. The castle’s witch, Alys Rivers, consistently intervenes in Daemon’s life. She’s mostly a positive influence, forcing Daemon to face his bizarre nightmares and midday hallucinations. Over time, this experience pushes Daemon away from his aspirations of conquering the throne. A brief dream conversation with his late brother, King Viserys, finally helps Daemon realize that the crown isn’t as appealing as it seems. The final straw comes when Alys summons Daemon to the castle’s godswood, a place of worship for followers of the old gods of the forest. The structure prominently features a heart tree. Harrenhal sits on the coast of the God’s Eye, only a few miles north of the Isle of Faces. While few ever visit the island, it’s possible that a visitor from the island could reach the mainland. BeforeDaemon has his final dreamsequence, the one that lets him watch a quick montage ofGame of Thronesscenes, he spots a Green Man sneaking away. He could be an agent of the three-eyed crow or a guardian of that tree.

Could more Green Men appear inHouse of the Dragon?

There’s at least one more scene inHouse of the Dragon’s source material that might include the Green Men. Addam of Hull, soon to be known as Addam Velaryon, will seek their advice. Addam might be the most decent man in the show. Hewins the dragon lotterywithout even entering and immediately proclaims his desire to use this power to do what he feels is the right thing. He’s honorable, loyal, indifferent to power, and thrilled to do whatever he can to serve his perception of the greater good. While trying to prove his devotion to the cause, Addamflies his dragonto the Isle of Faces to seek counsel from the Green Men. No one knows exactly what they told him. This version of the character might not need the help. This quote of his sums him up beautifully:

I have sweated blood in service of House Velaryon. I may appear lowborn, but I know much and more of service. And if the gods call me to greater things, who am I to refuse them?

House of the Dragonhas introduced an interesting element of the canon in a very quiet way.Daemon’s vision has a lotof implications that could be massive in future episodes. The Green Men are a minor detail of the franchise that could be a lot more important to older stories. They’re mostly lost to history, but the idea of human wizards protecting sacred trees sounds too good to leave in the margins.