This line of inquiry will be seen as nearly taboo by some, as death is a most sacred of passages, while others might greet it in earnest, as the passage brings them closer to the Mother. Those in Vanaheim will speak of it more clinically, while those in Alfheim might speak of it more spiritually. Hel will speak of it as a process where Tyr will speak of it as a journey ( and Freyr will just get sad and hug something ). Regardless of the source, however, he will find that all would claim the concept of "death" must first be understood from the point of "life" as it comes from the Mother.
Yosuke's findings introduce the basic concept of this, as well as the Eighth Doctor's, but all will emphasise the idea that life is magic that comes from the well at the heart of Yggdrasil. In the same vein as the law of conservation of energy, magic is never created or destroyed; as it comes from the well to birth either the smallest of insects or the greatest of beasts, it is returned to the well upon the creature's death.
This is the cycle of rebirth. Not the literal rebirth of a soul, as a soul enters this world only once ( naturally, all resurrections notwithstanding ), but the reuse of magic over and over to generate new life, each cycle different and unique yet irrevocably connected to the previous. This is the "connection" of all beings in Creation as the Mother's children - including the World Tree itself!
The death of the Tree is not the end of life; rather, it is the opportunity for new life to arise, as all of that magic would return to well to overflow once more and bring about new universes and beings to inhabit them. It may mirror the first iteration, but it will not replicate it. Once a soul is gone, that soul is gone forever.
The reason the Travellers can be resurrected is because their souls exist across two planes: this world, and their own world. That tether to their home world gives the gods the opportunity to prevent the dispersion of the Traveller's soul, so that it cannot return to the well of magic. This is why multiple resurrections come at a cost; the gods are actively fighting against the natural instinct of dispersion. This is also why the gods could resurrect Tyr and Freyr, but not Laufey, because Tyr and Freyr's souls were preserved and could not disperse back into the well, but the gods ensured that Laufey was granted safe passage back into the Mother's arms.
As for magic dying, the simplest of answers is "maybe". No one is really sure! Magic is a manifestation of will, not actual tangible power, as can be seen in Yosuke's research. Will is a persistent little shit, which means it could very well continue past the magus' expiration date if it was firmly rooted in reality. There's very little experimentation done around this hypothesis, which is why there's so much ambiguity surrounding it, so most results will turn up "it's possible" over a solid yes or no.
And lastly, any myths and rituals performed by the natives will all vary on their interpretation of the Mother as a being. Those that would call speaking of death taboo might favour burial, as it is quiet and solemn and puts the deceased's vessel in the earth to be as close to the Mother as possible. Those that would cherish death might favour celebrating it with song and dance and burning the body, to ensure the swifter dispersion of the deceased's soul to return to the well of magic. Most funeral rites seek to ensure the passage of the soul in one way or another, lest they end up like those trapped in Hel's district with earthly tethers that will leave them to fester halfway between the living and the dead. Hel's job as goddess of Niflheim is to ensure their passage, so she would speak of it as necessary and value any ritual that eases the dispersion of magic upon death.
WOW YOU GOT THE LONGEST RESPONSE I AM SO SORRY
Yosuke's findings introduce the basic concept of this, as well as the Eighth Doctor's, but all will emphasise the idea that life is magic that comes from the well at the heart of Yggdrasil. In the same vein as the law of conservation of energy, magic is never created or destroyed; as it comes from the well to birth either the smallest of insects or the greatest of beasts, it is returned to the well upon the creature's death.
This is the cycle of rebirth. Not the literal rebirth of a soul, as a soul enters this world only once ( naturally, all resurrections notwithstanding ), but the reuse of magic over and over to generate new life, each cycle different and unique yet irrevocably connected to the previous. This is the "connection" of all beings in Creation as the Mother's children - including the World Tree itself!
The death of the Tree is not the end of life; rather, it is the opportunity for new life to arise, as all of that magic would return to well to overflow once more and bring about new universes and beings to inhabit them. It may mirror the first iteration, but it will not replicate it. Once a soul is gone, that soul is gone forever.
The reason the Travellers can be resurrected is because their souls exist across two planes: this world, and their own world. That tether to their home world gives the gods the opportunity to prevent the dispersion of the Traveller's soul, so that it cannot return to the well of magic. This is why multiple resurrections come at a cost; the gods are actively fighting against the natural instinct of dispersion. This is also why the gods could resurrect Tyr and Freyr, but not Laufey, because Tyr and Freyr's souls were preserved and could not disperse back into the well, but the gods ensured that Laufey was granted safe passage back into the Mother's arms.
As for magic dying, the simplest of answers is "maybe". No one is really sure! Magic is a manifestation of will, not actual tangible power, as can be seen in Yosuke's research. Will is a persistent little shit, which means it could very well continue past the magus' expiration date if it was firmly rooted in reality. There's very little experimentation done around this hypothesis, which is why there's so much ambiguity surrounding it, so most results will turn up "it's possible" over a solid yes or no.
And lastly, any myths and rituals performed by the natives will all vary on their interpretation of the Mother as a being. Those that would call speaking of death taboo might favour burial, as it is quiet and solemn and puts the deceased's vessel in the earth to be as close to the Mother as possible. Those that would cherish death might favour celebrating it with song and dance and burning the body, to ensure the swifter dispersion of the deceased's soul to return to the well of magic. Most funeral rites seek to ensure the passage of the soul in one way or another, lest they end up like those trapped in Hel's district with earthly tethers that will leave them to fester halfway between the living and the dead. Hel's job as goddess of Niflheim is to ensure their passage, so she would speak of it as necessary and value any ritual that eases the dispersion of magic upon death.