Rune Magic
Rune Magic is the strongest form of Norse magic. Users of this form of magic can either carve the runes into objects (such as @Hearthstone Alderman's "runestone" tablets) or chant/sing the names and sounds of the runes (galdr) to cast spells.
Rune Effects
In addition to being a phonetic alphabet, each rune has it own name and a variety of esoteric meanings that represent the metaphysical concepts ("the genetic code") of the universe; to cast a spell, the user must understand the meanings of the runes and how they apply to their intended spell. For example, Raidho ("r") literally translates as "Ride" and is associated with travel ("the Journey"), motion, evolution, and rhythms; Hearthstone can use this rune to bend the fabric of space to create an "endless" loop to slow down @Gunilla and the @Valkyries. Thurisaz ("th") is "@Jotunn" and represents the giants, chaotic forces, aggression, destruction, and the thunder god Thor (who is of giant stock); when searching for Andvari's ring, Hearthstone used this rune to temporarily evaporate a river thirty feet deep. Perthro ("p") is "the Unknown" and represents fate, luck, mystery, occult powers, and an emptiness waiting to be filled; Hearthstone once used this rune to place himself and his friends in the hands of fate. @Blitzen, on one occasion, used Perthro and a combination of other runes to create a size-shifting carpet bag containing seemingly-limitless space.
Usage
To be able to perform it, one must go through great suffering: @Odin Borson hung from Yggdrasil for nine days with a spear in his side; Hearthstone was resented by his family, who blamed his deafness for causing his brother's death, and was treated as less than a slave. Rune magic is taxing for novices, as Hearth became faint whenever he would use a rune stone in battle.
List of Runes:
Ur: Ur or Uruz, is the Icelandic word for "rain" and Old English for "wild ox". It symbolizes "valor", "fortitude", "strength" and "stability".
Hearthstone used Ur on himself to gain an ox-like strength, stamina, and durability. His body transforms into a berserk-like form to handle the sudden surge of power.
Thurisaz: Thurisaz represents @Thor Odinson, god of thunder and strength. It can also be reconstructed as thorn and mean "giant". It symbolizes "masculinity", "courage", "empowerment".
While searching for the Ring of Andvari, Hearth dropped a Thurisaz into a small lake, causing it to absolutely evaporate in a violent discharge of destructive power.
Raido: Raido symbolizes "ride", "wheel", or "journey".
Used as the rune of spatial manipulation. Hearthstone first uses it to create a loop around Gunilla and her Valkyries to slow their chase after @Magnus Chase and his friends. He then used it to transport Magnus, Blitzen, and himself from @Alfheim to @Mortal Plane.
Kenaz: Kenaz represents @Loki Laufeyson, Father of Lies, and God of Fire, Magic, Mischief, Artifice and Stories. It symbolizes "torch", "passion", "inspiration", and "creativity".
Hearthstone created a floating rune made of fire to help his friends traversing through @Niflheim. According to Blitz, the fire of Kenaz is fueled by the caster's stamina.
Gebo: Gebo or Gyfu symbolizes "gift", "exchange", or "generosity".
Hearthstone casted Gebo to conjure dinner for Magnus and Blitz. It is unknown if Gebo can create other gifts besides food, but it's been confirmed that whatever is created via Gebo can't be used by the caster (as it's a gift from the caster).
Haglaz: Haglaz represents Urd, the Norn of the Past. It symbolizes "hailstorm", "cleansing", and "destruction".
Used by Hearthstone to conjure up a hailstorm.
Isa: Isa represents Verdandi, the Norn of the Present. It symbolizes "ice", "delay", "self-control", "frigidity".
Hearthstone first used Isa to (unsuccessfully) freeze @Utgard-Loki and prevent his escape from @Loki's Cavern. He then uses it later to freeze giants and draugr in the fight aboard the Naglfar.
Pertho: Pertho represents an empty cup waiting for being filled. It means "luck" or "fate".
Hearthstone used this at @Jötunheim to save Magnus and @Samirah al-Abbas, he also feels represented by this rune and puts it on the top of his staff.
Algiz: Algiz means "shielding".
Hearth used it to redraw the boundaries of @Fenris's prison.
Tiwaz: Tiwaz represents the god @Tyr. It means "sacrifice".
Hearthstone used this against Fenrir to save Blitzen sacrificing his strength.