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Warning! This page contains spoilers for The Ship of the Dead.
Hearthstone was born in Alfheim and was rejected by his parents because of his deafness. When he was eight, his brother Andiron was killed by a brunnmigi, a shapeshifter that lives in wells. He couldn't hear him due to his deafness. Their father killed the beast but made Hearthstone skin it, they placed the pelt in his room as a reminder to pay his brother's wergild, a debt that must be paid to the deceased. His parents said Andiron should have lived while he should have died. They placed dry erase boards in his room for chores and rewards, chores were granted a small amount of gold while rewards cost a large amount of gold.
While trying to practice rune magic, Hearthstone accidentally landed in Nidavellir. Since elves can only be in light, he could've died but was saved by Blitzen. In Blitzen's home there is a tanning bed that he might've made for him.
When Hearth drank from Mimir's well he was given two choices. One was to gain the ability to hear and be accepted, the other was to practice magic. He couldn't have both. Hearthstone ultimately chose to practice magic. While under Mimir's service, he was tasked along with Blitzen to watch over Magnus. He took the day shifts, as he needed light to survive, while Blitz took the night.
After breaking into his uncle Randolph Chase's house, Magnus looks outside the office window and sees Hearth standing next to a statue of Leif Erikson. Hearth uses sign language to try to tell Magnus to get out of the house, but it was too late as Randolph returns home and comes upon Magnus and tells him that they don't have much time and "they" are coming to kill Magnus now that he's sixteen. Hearth steals a cupid bow and arrow at a local toy store and attacks Surt with Blitz in order to protect Magnus. Hearthstone was swatted away and lands by the railing. He helps a woman get her children out of their stroller and takes them to safety at Magnus' urging.
He and Blitz find Magnus in his room at Hotel Valhalla. Before they can explain why they where watching him, the squirrel alarm sounds. They flee to Midgard while Magnus' hall mates distract the wolves and the Valkyries, they land in Fenway. He and Blitz explain that they were told that he was a son of Frey and to watch him. They show him his obituary and the three plan to sneak in to the funeral home before his service starts. He and Magnus plan to meet up with Blitz on the first T stop on Arlington after they get the sword. When on their way to the funeral home, they spot Gomez, a police officer who knows them, and hide. He explains Alfheim to Magnus while they hide. While at the funeral home he stands watch while Magnus finds the sword. He is knocked out and wakes up in an alley. He hobbles into the funeral home and gets Magnus. The two then meet up with Blitz and tell him the sword was not there. They then spot Sam and follow her. When they lose her they decide to go to the charles, Sam then attacks them. He and the former Valkyrie fight until Magnus disarms her. They then let Sam join them. The four then head to a dock where Blitz throws Mimir's head in the water to hydrate it. He and Sam bow in his presence. After that he tells them to find the sword and that they have a week to do it. He offers them knowledge in exchange for their service, but they decline. After Mimir leaves, they talk it over during lunch.
When they get to the transportation building's food court, he and Blitz grab a seat and have an argument in sign language. When Sam and Magnus get back, a pigeon threatens to starve them unless he listens to them about the sword. Magnus agrees despite the others urging not to. The pigeon gets their food in the form of an eagle and eats the whole thing. Sam then claims it a jotnar. When it takes off with Magnus they follow them and find him in the Boston public library. When he gets down and tells them what he learned they reprehend him for making a deal with a jotnar nut to go fishing.
When they get to the docks he and Blitz are denied the boat while Sam and Magnus are allowed on it. He stays behind to help Blitz find shelter and agrees to meet the demigods at the library later. During that time he and Blitz do research as to what to do next. They wait for Magnus at the public library and talk with Big Boy while they wait. When he leaves Magnus appears. The three compare notes and Blitz is worried. The Dwarf gives them sandwiches and sleeping bags. Hearth is the first to go to sleep.
In the morning he, Blitz, and Magnus meet up with Sam in the public garden to get to Nidavellir. While Magnus is opening the rift he casts a spell to keep the advancing Valkyries and Einherjar from catching them but collapses soon after. When Magnus opens the rift he is aided by Sam and Magnus into it. The four climb the world tree until they find a knothole the sword wants to enter. He gets stuck and before they can free him, Ratatosk, a huge squirrel appears. Blitz drags Magnus into the knothole while Sam hides him and herself in her hijab.
While they hide he helps Sam along as she is recovering from the squirrel's shrieks, as it's shrieks are insulting. They wonder around the world tree and avoid getting attacked by deer until they reach Alfheim, much to his displeasure. They meet up with Magnus and Blitz in Nidavellir where he hugs Blitz and the four fill each other in. Blitz then tells them Junior challenged him to a crafting contest, loser gets decapitated. After that Blitz takes him and the demigods to his apartment. Blitzen is asked about his story, and Hearthstone tries to stop Blitz from telling his story, which the dwarf says he is fine with sharing. After Blitz heads to his room he tells Sam and Magnus that Blitz is good at crafting but not under pressure and shows them the tanning bed Blitz made for him. He signs that people cheat in the contest, but they can get away with it if they make it look like accidents. He suggests Sam do what she did on the World Tree, she leaves in rage when she hears it. He does not answer Magnus when he asks what that was about and heads for the tanning bed. During the competition he alternates between aiding Blitz and standing guard. When Magnus asks him about Sam, he does not answer. When Blitzen was declared the winner he jumped for joy. After getting the earrings and rope it was discovered Junior lied about knowing the location of the Fenris Wolf's island and saying it was classified information but that Thor might know. He and the others ran for their lives when Junior claimed Sam was a shapeshifter and says she cheated. While running the others duck into an alleyway but he keeps running, he meets up with the demigods and asks where Blitz is and notices the sword is floating. After an explanation he shows them a river leading out of Nidavellir. The three jump when the dwarves find them.
Magnus heals Hearth but senses a lot of grief. The elf tells him he will tell him later. He gets nauseous in the dimly lit Jotunheim. He suggests that they use Jack to find Thor and he rides Otis along the way. Hearth gives Magnus a perthro rune to hold as he rides Otis. When they meet Otis' brother Marvin he says Thor is drowning and pleads to save him, or he'll threaten to kill them. When Magnus slays the giantess attacking Thor he is splashed into a tree and invited to dinner by the Thunder God along with Sam and Magnus, which is Marvin and Otis. Hearth signs that he thinks Thor is annoying but Thor thinks he is complimenting him. He is then assigned to find Mjolnir. He aids Blitz when he falls out of a tree and shares a tent with him.
Hearth leaves Otis and Marvin's head by Thor when they head out. They spend the day climbing a cliff to get to Geirrod's fortress. Once they get to the top they rest and discuss how to get across the chasm. He summons one of Sleipnir's sons but passes out in the process. He is aided on to the horse who jumps off the cliff. He regains consciousness when Stanley lands and is helped off the horse whlie signing out random words. He stays behind with Blitzen as a backup. He and Blitzen free Gunilla- who he holds, and help Sam and Magnus. The five ran into Gerriod and barter for Thor's weapon. The giant agrees in they play catch with him. They anger him and he throws hot coals at them. He dodges them until Magnus causes Geirrod to collapse the ceiling on himself. He dusts himself off and signs complaints to Magnus, who notices Gunilla is gone. He tries to use rune magic against her but she threatens to kill Blitz if he does. He distracts Gunilla by pointing and Sam sends her back to Valhalla. They retrieve Thor's staff and the Thunder God appears. Hearthstone signs his annoyance that Thor can not help them fight Fenris wolf, which Thor again thinks is a compliment. The God sends them where they need to be.
Hearthstone wounds up at Mimir's well. The head said that Hearthstone was now a master of Alf Seidr and gave him a two-pronged staff made of polished oak. He meets up with Blitzen, Magnus, and Sam at Long Wharf. Magnus gives him the Perthro rune, which he attaches to his staff. The four find the dwarf brothers and Blitz says they will try to rob, kill and abandon them. They buy four tickets regardless. Along they way he is practicing summoning and banishing his staff. When they dock he and the others are left on the island to face the wolf.
When they find the wolf he is the only one unaffected by his taunts. He stops the others from approaching him. Soon after Gunilla appears along with two other Valkyries and Magnus' hall mates. When Gunilla orders their arrest Magnus's hall mates refuse. Then Surt arrives and ignites his staff in golden fire. He goes with Magnus, Sam, and Blitzen to re-bind the wolf. Hearthstone uses a shield spell to create more heather. When Fenris slashes Blitzen's throat he uses his strength to form a barrier between Blitzen and the wolf and brands the symbol of Tyr on the wolf's forehead. He aids Blitzen in getting to Magnus and Sam when they re-tie the wolf. When the island starts to fade he and the others race to the shoreline. When T.J. pulls out a Frey Boat everyone gets on. He and Blitz have an argument in sign language about who had a dumber plan but were too tired and ended up having a poking contest.
When they arrive at the hotel they are escorted to the feast hall to have judgment passed. The thanes call him Blitz and Sam Magnus's questionable companions. Just as the thanes are about to pass judgment X reveals himself to be Odin. Once the all-father explains what he has been doing the past two years he awards Magnus and his friends. He offers Hearthstone private lessons with himself to hone his skills in rune magic. Hearth is shocked and accepts Odin's offer. He grants Hearth full access to all nine of the worlds.
He attends the funeral for the fallen Valkyries held in the public garden. He is excited about studying under Odin and agrees to help Blitzen move into his store.
Hearthstone and Blitzen have been hiding out in one of Mimir's safe houses. After one of his private lessons with Odin, he predicted that Blitz would die on a mission. He and Blitz met up with Sam and Magnus in Provincetown to retrieve Mjolnir. He tells them that this is dangerous for Blitzen but finds that he is the best person to find the hammer. When they find the wights tomb he opens it, however, they fall in and he breaks his ankle. After Magnus heals him he investigates an iron coffin and opens it with a rune stone. Hearth stops cold in his tracks when he sees Gelir's sword, Skofnung. He warns his friends about the blade and readies himself for battle when the zombies draw their swords. Hearth uses the uruz rune to increase his size and strength. He destroys the draugrs and Gellir before Magnus calms him down. After that, Loki and Randolph appear. He clings to Blitzen when the sword is drawn and is shocked when Blitzen is stabbed. He cradles his wounded friend and blames Sam for this.
He, Sam, Magnus and a petrified Blitzen head to the Provincetown Airport. He is angry about what happened to Blitz and would not talk. He used the last of his magic to summon bubble wrap and tape to keep his friend safe. When Barry and Amir arrive he recognizes Hearth as one of Sam's 'math friends'. He puts Blitz on the plane before they fly off to his home world. As they are about to take off, he is confused by everyone's reaction to Barry. He sits across from Blitz and looks worried about his friend. Before he and Magnus jump, he straps Blitz to him with his scarf.
They land on the Makepeice property and he gives Magnus sunglasses to block out most of the bright light. On the way to his house they are stopped by two police officers. They asked him if he was on the Makepiece property. Once Magnus says he is deaf, they recognize Hearth as Alderman's son. They then take the two to Hearth's father. When they arrive home they are greeted by Inge, one of the housing staff. His father then arrives and berates him for using ASL and invites his son and the son of Frey in. When he signs, his father tells him to use the slab. He tells Hearth that since he left, his mother has died. He is reassured by Magnus that he is with him. He and Magnus are led to his old room. Magnus is shocked and angered by what his friends parents had him do. Inge suggests they rob the Careful One, a dwarf living in Alfheim. Hearth says it is to dangerous and they could easily die, but Inge has faith in him. The next morning Inge told them where to find the Careful One. He hugged her goodbye and she went away blushing. Magnus teased him about this before they left.They eventually came across the well where his brother died. They move on after a short pause and eventually come across a promising waterfall. He summons the rune of Thor and blows the river sky high, but becomes more aggressive. Magnus, fearing that innocent fish will die, searches for Andvari and finds him. They bring the dwarf out of the river and return it to normal. The dwarf then tell them he will destroy them. After a brief interrogation, Andvari give them the gold and a cursed ring. He leaves and He and Magnus take the gold to his father.They arrive back at his house and pay off the wergild, only to find that they are a coin short. They show his father the cursed ring and try to warn him to no avail. Hearthstone unpetrifies Blitz, uses the Snoknung stone to heal his wound and hugs him. After a while, his room is cleared of whiteboards and his mattress, and he is told the party has started. They see his father wooing the guests with his fortune. Hearth asks him to take the ring off, but he does not and insists Hearth is jealous of his fortune. Hearth summons a storm to break all the windows, allowing the guests to escape. Before he leaves, Hearth frees Inge from his family's services and she kisses him on the cheek. He follows his friends through a portal to another world. The three of the land in a stairwell in Midgard. He is wounded by the police and then healed by Magnus. Hearth worries for his father's sanity. He goes with Blitz to Nidavillir for the night.
The next day he, Blitz, Sam, and Stanley wait for Magnus and Alex at the park. He is wary of Alex at first due to her/him being a child of Loki, but Magnus reassures him. While the others ride Stanley to get to Jotunheim, he flies with Sam. The two of them arrive at Utgard-Loki's palace a day before the others and claim guest rights. They were nearly killed seven times and tricked with illusions. The others eventually show up and the king releases them, he also tells them that they must compete in a tournament to gain the giant's trust and the information they need or die trying. They discuss strategy until the giant king comes over to them and says that an alliance between Loki and Thrym would oust him as king. after Sam deduces that her opponent is fear itself. A giant challenges him to a ball game, the giant scores a thousand in skiball while Hearth scores over five million in pinball. After Blitz wins his challenge and Alex and Magnus tie, Utgard-Loki tells them that Loki plans to use the Snofnung Sword and Stone to free himself. He tells them that he could have given them two choices: either die at that moment or find the hammer themselves before the giants give chase at the end of the five minutes they had to speak with Utgard-Loki.
Before they can be killed, he Andy his group are saved by the goddess Sif. She gives him a bag of runes made of Rowan. But says it is missing the inheritance rune and that he will one day have to retrieve it. She sends them to find Thor and tell him of the information they have on mjolnir. They meet up with Thor and explain everything to him while the thunder god misinterpreted his signs. While Sam, Alex and Magnus get ready for the wedding. He and Blitz are given a pass by the thunder god to let them into Valhalla to recruit einharjar.
He, Blitz, T.J., Mallory and Halfborn arrive in Loki's chambers and fight the giants. He freezes the last of Loki bonds, but Randolph chips away at it before the last of the restreints are cut, freeing Loki. He watches as the tricker kills his serpent warden and flees as the gods arrive. He thinks that he would have been able to stop Loki if he had all his runes. He signs with Vidar about hearing people.
Back at Valhalla, he is to distracted by Loki's escape to enjoy the feast. Helgi asks him and his friends to come to his office. He tasks him and his friends with capturing and rebinding Loki. He and Blitz spend the night in Magnus' suite. He is the first to fall asleep. He is gone by the morning leaving a bed of daisies in his place.
He and Blitz were waiting to be picked up when they were attacked by a sea monster who, unknown to them, wat the pet of the Nine Billow Maidens. Hearth and Blitz are then taken captive by Aegir, who plans to eat them. Their friends manage to free them. Just as they are about to eat one of Aegir's daughters calls out Magnus. After they get Aegir to talk about mead, he explains to Magnus what flyting is. After they convince Aegir not to kill them, he decides to let them escape if his daughters can't catch them. He uses his lagaz rune to turn the maidens into puddles for a few seconds. Magnus tells him to use it to take out a wall, which he does when Njord arrives, and they escape.
They surface and he, Magnus and Blitz speak with Njord. He tells them that they should got to skadi's harbor, as it is the safest passage, and to get Kvasir's mead, to help with the flyting with Loki. He also tells them that he and Blitz could die getting the mead. Njord tells them that he and Blitzen must find Bolverk's whetstone. They agree after some debate and tell Magnus he can meet up with them later. They say goodbye to Magnus and Njord sends them away.
He and Blitz scout out the ruins of his father's mansion, which he has no legal rights to, before the two materialize on the Big Banana and tell Magnus they need his help dealing with his father. They return and venture deep onto the property and find a cave; they then know Alderman is in. His father emerges momentarily from the cave in the form of a dragon. Hearth says the only way to stop Alderman is to kill him. He volunteers for the act, but is discouraged by Blitzen when the dwarf says it would taint his wyrd. They decide to let Magnus and Jack do the deed. He picks up the othelo ruin by his brother's grave and plans to switch as a distraction. He practices his magic until it is time. He summons his brother's spirit to distract Alderman and when his father charges at them Blitz defends him. He says goodbye to his brother and confronts his dying father. He frees Jack and asks the sword to cut out his father's heart so he could cook and eat it. He decides to eat the heart to learn more about his father and asks Magnus to take over so he could sign easier. Magnus accidentally destroys the heart and takes in the blood. Hearth looks angry yet relieved and they head back to the big banana.
They return and tell the crew about what happened and they give him their condolences. He and Blitz head below deck to sleep and they stay back when the other scout Flåm for a train station. He and Blitz sleep through Baugi's attack and learn about the attack when they wake up. They leave Flåm and reach Jotunheim by morning.
He summons a fire to keep everyone warm. They decide to walk to shore when the ship can not get past the ice. His fire gives out when they reach shore and they are invited in by Skadi to explain themselves. They bath and have a hot meal while they explain what they are planning. Hearth is pleased Skadi knows Alf Sign Language. She tells them Loki will launch Naglfar by noon the following day. She lets them spend the night. When Magnus wakes him up he signs I am not here before giving in to the son of Frey. They eat breakfast and get ready to ski to Naglfar.
When they reach the ship he, Blitz, T.J., Halfborn and Mallory separate to give Magnus time to flyt Loki. He gives her m his Othela rune and head out to put their plan in motion. He summons the Thurisaz rune to strike fear into his enemies and vaporize a few, and the Isa rune to freeze half the ship.When a ceasefire for the flyting is called he is supported by Blitz and they watch the match. He looks at Magnus concerned but is pleased with the complement about being the greatest rune magician in the Nine Worlds. Magnus reveals to the giants that he faced his father when he turned into a dragon, overcame Alderman's abuse with his mother and his brother's death, and broke a curse. He carries Blitzen on his shoulders and he summons Stanley with a rune. The group jumps off at Sam's request and land on the backs of water horses who swim out of the harbor just as it is freezing over.
They spend three days at sea. During this time he and Blitz make sure everyone has what they need. He and T.J. talk about his war stories. They land on Vigridr, where the chosen of Odin will die during Ragnorok, and are greeted by the gods. Odin applauds his use of magic during the final battle and gives him a signed copy of his new memoir. When they return to Valhalla Helgi makes him and Blitz honor einharjar. They leave and agree to meet Magnus the next day for his plans for the mansion.
He and Blitz help out at the Chase Space, working as cooks and he teaches the kids Sign Language. He cooks food for the Fourth of July on the roof.
Hearthstone is a tall pale elf with short, spiky hair so blonde it's almost white and pale gray eyes. He wears a black leather jacket, black motorcycle pants and pointy-toed shoes, and a red and white striped scarf. After losing said scarf in The Ship of the Dead, Alex Fierro gives him a pink and green scarf as a replacement.
Later on, Magnus begins to notice the non-human details in Hearth's appearance - the elf's pupils are strangely reflective, like a cat’s, while his veins are more green than blue under his translucent skin. Also, despite his disheveled appearance at times, Hearth does not ever reek like a normal homeless person – body odor, alcohol, stale grease. Instead, the elf smelled more like pine needles and woodsmoke.
Hearth is a very loyal friend and has risked his own life multiple times to save both Magnus and Blitzen. He is shown to have a dry and self-deprecating sense of humour which he often exercises when annoyed or happy. He is guarded with his own emotions as he was constantly downtrodden and ridiculed by his father and the elves around him due to inability to hear (as elves cannot tolerate imperfections). However, with Magnus and Blitzen his personality and self-confidence evolves as he is around people who truly appreciate his talents and empathise with his weaknesses.
- Alf Sign Language: As Hearthstone is deaf and mute he is able to communicate via Alfheim Sign Language. It also happens to be the same as American Sign Language.
- Rune Magic: Hearth is proficient at rune magic, having been taught to use these powers by Odin himself. With his runes, he can bend the very fabric of the universe, make time slow down, invoke destructive force with Thurizaz or make himself stronger with Uruz. However, the casting of these runes leaves Hearth drained but he is gaining proficiency to stop himself from doing so.
- Deafness/Audiokinetic Immunity: While Hearthstone can not hear, his lack of hearing gives him an immunity to sound-based attacks. Such as when he and Sam were hiding from Ratatosk and he was unaffected by the squirrel's screech. This also protected him from Fenris Wolf's taunts, and later the security Nøkks' mournful music at his father's party.
- Lip-reading: Being deaf, Hearth had to learn how to read lips in order to understand and communicate with other people.
- Archery: It is revealed in The Sword of Summer, that Hearth is skilled in archery. We see a limited exhibition of this characteristic when he fights Surt with a toy set of bow and arrows.
- Pinball Skills: Hearth has a talent when it came to pinball.
- Runestones: Hearth uses rune stones to cast spells.
- Staff: When Mimir told Hearthstone that he was a master of Alf Seidr, he was given a white oak two-pronged staff which now holds the rune most meaningful to him: Perthro, the empty cup.
- Rowan-Wooden Runes: Given to him by Sif, their magic is supple and malleable and easier to use than his stone runes.
- Hearth is deaf and knows Alf Sign Language, which abbreviates to ASL.
- It is stated that his parents never accepted Hearthstone due to his deafness, as well the death of his brother.
- Magnus mentions that Hearth cannot read lips well while moving and that it required his full focus.
- According to Blitzen, he snores.
- Hearthstone is skilled at playing pinball. His skills earn him the title of "Pinball Wizard" by Blitzen.
- Hearth's "pinball wizard" title may be a reference to the 1979 song by the Who: the song sings about a deaf and dumb pinball player, and that matches Hearth's description.