I'm in love with the concept of Merlin's magic being deeply tied to nature, more specifically the wheel of the year and seasons. And I would love that to be something he explores post-5x13. Just things like....
— His magic is practically bursting out of him on the Sabbats. He wakes up with the dawn on every one, and the rest of the day is just a fight to keep him from exploding with the energy of everything around him. Those are the days he always finds it hardest to keep his magic hidden, but no one ever seems to notice things that definitely should get him caught on those days.
— On the spring and summer festivals (Imbolc, Ostare, Beltane) he sometimes wakes up with literal flowers everywhere around his room and twisted around his body in all different colours (appropriate to the season). They're glowing faintly, and everywhere in his room, and he has no idea where they're coming from, but they're the most vibrant flowers he's ever seen (and sometimes he gifts them to Gwen to mark the day, because she's still his oldest friend in Camelot, and he likes that the flowers make her smile).
— Every time he sees an animal die, he can feel it. It doesn't hurt, it isn't necessarily sad, but he feels the soul shift between the veils and he silently thanks them (if they were hunted) and wishes them well.
— On Litha (midsummer's day/summer solstice), he's been known to wake up literally glowing gold with the sunrise, and it doesn't fade until the sun is higher in the sky, which has been a bit of a problem in the past. His magic is deeply connected to the ancient workings of the world, and in that moment he is the sun itself.
— On cross quarter days, when the veil between worlds is thinnest, he can sometimes see through to far more magical worlds, or see what isn't technically there. He learns not to mind it. Some of the things he sees are beautiful.
— This is especially true on Samhain, where the veil between the living and the dead is thin, and while the spirit world cannot touch him, he can feel and sense them too. After Arthur's death, when he can be more open with his magic, and when he knows far more of the dead closely, he can sense them there on that day. Sometimes he'll turn and almost see someone, and smile and just bid Lancelot or Gwaine a "hello" before they have to leave again, only being able to pass through for a moment. Sometimes it's others — as the years go by, his mother, Gaius, Gwen, the other knights, pass on as well, and he sometimes sees them too. But never Arthur, because Arthur isn't there. He's not dead, only sleeping.
— Between Samhain and Yule is dead time, when the world is descending into the depths of winter, and the world is sleeping. Merlin still has as much power then as ever, but it seems dampened, for that month and a half. It is quieter, more reluctant to be called to his needs, as if it is taking a nap, just like the natural world.
— Yule is one of his favourite Sabbats, being so close to his birthday (yes I'm crossing HCs here), but also because when his magic wakes up, it's at its purest and most beautiful. And even though the day is cold, there's a warmth, the feel that summer will soon return. The snow sparkles with sunlight even when the clouds mask the sky. and it blankets a sleeping world that is slowly starting to wake up.
Merlin sometimes asks other sorcerers if they feel all this, and he speaks about it at length with the druids. They tell him that they sense it, but they don't experience it, they don't become it in the way that he does, no matter how in tune with the earth they are.
Because Merlin does not just have magic, it's not just a part of him that he carries, as it is for the rest of them. It is intertwined with his very soul, it couldn't be removed. He is the son of the earth, the sea, the sky, and just like a mother's blood runs in her sons veins, so are his veins alight with the magic that creates him. The Earth itself is tied into his bones, and with all the strange and sometimes annoying things that come with that, it's the most beautiful thing he could ever imagine.
