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Warning! This page contains spoilers for The Ship of the Dead.
Alex Fierro is a genderfluid, formerly homeless teenager from Boston, Massachusetts. She is the Norse demigod child of the god Loki (in female form) and Mr. Fierro. After dying and being chosen to become an einherji by his half-sister, Samirah al-Abbas, he is now the newest named resident of the Hotel Valhalla and a hallmate to Magnus Chase and the other people on Floor Nineteen.
Alex’s family is influential, which first attracted Loki's attention, causing him to seduce Alex's father in the form of a "voluptuous red-head". Nine months later, Loki left him with a child. The family didn't take the news well, especially after Loki permanently "opened their eyes" and made them aware of the Nine Worlds and the Norse gods. Alex spent her/his life being resented for her Norse heritage and for her gender fluidity, which was thought to be Loki's fault. Only her grandfather accepted her for who she was, and taught her how to make pottery.
About two years before becoming an einherji, Alex became homeless and began to wander the streets of Boston. At some point in life, he lived in a youth shelter on Winter Street in Boston, at roughly the same time when Magnus was there. He remembers hating the place.
Alex Fierro is first indirectly mentioned by Samirah, as the latter receives a message about a potential code three-eight-one: heroic death in progress. This prompts her to run out of a meeting with Magnus and an informant (which turns out to be Otis). Samirah initially refers to Alex as her brother, implying that he was male when he died.
After Magnus comes back to Hotel Valhalla, Hunding mentions that a newly arrived "monster" attacked him, after being shown her new room, which completely fouled Helgi the manager's mood. Hunding is also the first one to call Alex an argr. When Magnus arrives at the Nineteenth Floor, Alex – in the form of a cheetah and chased by the rest of the residents – charges at him, promptly knocking him back and puncturing several holes in his sneakers. It is revealed that she has been given X's old room and isn't exactly happy about it, leaving the place in ruins. When the group explores the room, they find broken pieces of ceramics, all decorated with the symbol of Loki – two snakes curled up in an elaborate S pattern.
Alex finally makes his full appearance during a combat exercise. As a weasel, she is carried in a burlap sack by one of Odin's ravens. After returning to her human form, she states that she's calmed down already and will not try to "mess anyone up". As the combat starts, and the dragons are released, Alex accompanies the rest of the Nineteenth Floor, and is asked about the shelter on Winter Street by Magnus. She explains that having been in the same shelter does not make them friends, as the group is attacked by an elder lindworm called Grimwolf. Alex deduces that it was Loki that somehow unleashed the monster inside Valhalla, and she attacks the dragon along with the group. As Magnus is distracted by a splinter of Loki's consciousness, Alex kills the dragon with her steel wire. Later on, Loki is seen channeling his energy through Magnus, which will kill him and subsequently blow up quarter of the training ground. Seeing no other option, Alex decapitates Magnus with her garrote.
Alex is later seen sitting next to Sam at the Thanes' table, waiting for her final moments to be revealed. Neither she nor Sam are very comfortable with the Valkyrie Vision video: it started to record much earlier than Samirah intended, and it shows Samirah's embarrassing conversation with her grandparents and the Fadlans. The action moves to Alex, saving an older man from wolves – sons of Fenris. The man, a Norse demigod in denial, refuses to fight and leaves Alex alone, which results in the latter's death. Alex is then chosen by Samirah and brought to Hotel Valhalla. The video leaves the thanes and the einherjar in awe. They applaud to Alex for her bravery, and accept her into Valhalla, despite her being both a child of Loki and an argr. Later, Magnus sees Alex accompanied by the people from the Nineteenth Floor, as he talks with Sam. During their discussion, Sam reveals that Alex was initially very hostile when rescued as he thought that becoming an einherjar would restrict him to a single gender.
Alex, now male, is later seen with Halfborn Gunderson as they accompany Samirah and Amir Fadlan. Due to Loki's schemes, Sam's grandparents and the Fadlan family have learned about the Norse gods and their connection to Sam, so Sam attempts to show Amir the Bifrost Bridge to better his understanding of their world. As her half-brother, Alex volunteers to be a chaperone to Sam, and he himself is chaperoned by Halfborn. After Amir is shown the Bridge, all of them are invited to meet Heimdall, but Halfborn decides to stay behind. During the meeting, Alex lies on the Bridge and makes "light angels". After learning about the location of Thor's hammer, Heimdall drops all of them off next to the Fadlans' restaurant. Alex joins Magnus, Sam and Amir for dinner as they discuss the consequences of Sam's grandparents learning about the Nine Worlds. Later, Magnus and Alex get back to Hotel Valhalla, but not before Alex wisely asks for a doggie bag to pack up the leftover falafel.
The next morning, they visit Randolph's house in Midgard to look for clues that might lead them to Thrym. Magnus and Alex, currently female, engage in a conversation regarding Alex's gender fluidity, and Alex explains to Magnus that the word she does not identify as non-binary and does not like to be referred to using they/them pronouns. Soon after, they find a photo of Bridal Veil Falls, which they believe is where Sam is about to get married. Magnus and Alex regroup with Sam, Hearth, and Blitz soon afterwards. With the aid of Stanley, the two travel to Jotunheim along with Blitz, where they aim to find Utgard-Loki. After an encounter with a giant called Tiny, whose colossal bag they must carry, Alex tells Magnus about the circumstances of her birth.
When Blitzen has altered the bag to shrink down to normal size, the trio head to Utgard-Loki's palace, where they reunite with Sam and Hearth. Alex and Magnus are tasked with defeating a pair of giants at bowling, in a contest at Utgard Lanes. However, the giants cast an illusion on the lane of the einherjar, making their bowling balls travel through a portal that connects to Midgard's White Mountains. The giant duo roll two perfect frames, while Magnus and Alex's own rolls cannot connect with the pins. During their final frame, Alex joins hands with Magnus to dispel the illusory portal together. Magnus bowls a perfect frame, while for their frame Alex shapeshifts into an elephant and knocks over all the pins. They subsequently win the contest.
After Utgard-Loki gives them the information they need to retrieve Thor’s hammer, the group is chased by Utgard-Loki’s giants but are almost immediately saved by the goddess Sif, wife of Thor. Sif teleports them to their home in Asgard where Thor also resides via Yggdrasil, and presents Hearth with a bag of runes as a gift. As she rides the elevator with her friends to Thor’s “man-cave”, Alex expresses her initial dislike for Sif, and agrees with Samirah when the latter says that the goddess is both dense and vain. Later, after discussing the retrieval of Mjolnir with Thor, Alex offers to pretend to be Thrym's bride in Samirah’s place, due to the oath of marriage that Sam swore with Amir on the Bifrost as well as her confidence in her ability to be immune to Loki’s powers. When Thor argues that she is an argr and not a “proper girl”, Alex retorts that she is gender fluid and well suited for the task.
The next morning, Alex is dressed in preparation for her “wedding” by Sif, after which her opinion of the goddess changes. Sif also warms to Alex. After the goddess Sif gets Alex dressed and they come out, Magnus is left awestruck seeing Alex as she looks beautiful. Magnus and Sam also get ready for the wedding as the chaperone and the bridesmaid, and Alex teased Magnus about his costume. After that, Sif opens them a portal to Taco Bell where Thor's chariot is waiting.
The trio arrives at Thrym's home, where the giants hold a wedding feast. After the feast, since the father of the bride must be present, the giants tunnel down into the cavern where Loki is held prisoner. Alex manages to keep up the act throughout the ceremony. When Loki asks Randolph to cut his binds with the Skofnung Sword, Alex reveals herself and attacks Thrym, while Magnus and Samirah take on the rest of the giants. They eventually defeat the giants – with help arriving in the form of Thor, Blitzen, Hearthstone, Mallory Keen, Halfborn Gunderson, and T.J. – but Loki escapes. Alex later tells Magnus that Loki, during the fight, willed her to die.
Back at Hotel Valhalla, Alex offers to help Samirah learn to resist Loki's control, but she refuses, to Alex’s hurt. She, Samirah, Magnus, Blitzen, and Hearthstone are tasked by Helgi, on Odin's raven's orders, to recapture Loki. Alex then storms off to her room, where she begins working on a clay trophy as a gift for Sif. The next morning, Magnus pays a visit to Alex, now male. He admits that Sam can resist Loki's power by accepting shape shifting and using it as frequently as Alex does. By the end of their conversation, Alex has shifted to female, and Magnus knows before he is told. Alex throws a piece of pottery she had made the night before at him as he walks out.
Alex helps Magnus train at Boston Harbor for his coming quest to re-imprison Loki. He is with Annabeth watching Percy train the sun of Frey and takes him back to Valhalla whenever he gets a fatal injury. The four have lunch and they talk about their plan to stop Loki. Alex says they should have set sail already and if they are to make it they should set sail by the end of the week. After the Greek demigods leave, he and Magnus head to the Chase Mansion.
When they arrive they find the doors blown in and a wolf corpse in the foyer. They explore the mansion and look to see if Randolph had a plan to take our Loki. When they reach the library on the top floor he sees a wolf on the roof and calls Magnus over. The decide to let the wolf in and see if it is looking for the same thing as them. He turns into a wolf and stares down the wolf before it takes a drinking horn by the fire place. Alex decapitates it and they find a journal in it. They decider it on the roof as a plan to defeat Loki. Alex mentions that her training with Sam to block out Loki is not going well and that something is going on with her but he will not tell. A raven delivers a message from T.J. saying they are about to set sail. Alex turns into a flamingo and flies of to get Sam.
He and Sam are picked up by the crew and set sail to pick up Blitz and Hearth. Soon after they leave they are dragged under water by nine women coming out of the water. They surface in a soup pot and are fished out by Aegir. He grants them guest rights and invites them for a meal, which consists of Blitz and Hearth. He states that he cannot eat dwarves and elves so Aegir releases them. He and Sam devise a plan. Just as they are about to eat, one of Aegir's daughters calls out Magnus. During a standoff between Aegir and the crew of the Big Banana. He signs to Magnus about talking to Aegir about mead. When their host agrees to let them go if they can escape he leaves and his daughters attack. During the fight he takes the form of a silver back gorilla. He helps out Magnus and Sam before Njord appears and allows Hearthstone to take out a wall so they could escape. When they surface Alex has changed gender and lets everyone know. She goes bellow deck to get food while Njord talks with Magnus, Blitz and Hearth.
A few days later she wakes Magnus to help out with Sam's training. At first she shouts the animal she wants Sam to turn into before having her half-sister face of against both Magnus and Jack. They stop after a while and she and Sam have a side conversation. She shakes Magnus awake when they arrive at York.
She, Magnus and T.J. go ashore while Mallory, Halfborn and Sam watch the boat. They run into Hrungnir and he challenges them to a contest at dawn. When he leads Alex searches desperately for a pottery studio. She rents one out for the day with my new she wired from her family. She puts T.J. and Magnus to work and she handles the potter's wheel. She tells Magnus about her family history and her relationships with her father and grandfather. She tells Magnus to call Sam and update her on their current events. They have dinner at a fish and chips restaurant and return to the pottery studio for the night. She takes the chair while Magnus and T.J. make makeshift beds in the back. In the morning she brings her clay warrior, Pottery Barn, to life and they head out to face Hrungnir. The meet the jotnar in King's Sqare and he fight begins. She pulls Potter Barn out of Hrungnir's clay warrior and is immediately engulfed by the clay being. She is healed by Magnus and thanks Pottery Barn when they are defeated. When T.J. defeats Hrungnir the giant tells tells them the mead is heavily guarded in Flåm, Norway. After T.J. stabs the giant in the heart it explodes and they head back to the big banana. The three return to the ship and head for Norway.
When Magnus, Hearth and Blitz return they tell them about their time in Alfheim. The crew is concerned about Magnus, but Mallory eases their worry. They arrive in Flåm and dock the ship. She goes with T.J. and Halfborn in one direction to find the train station while Magnus, Sam and Mallory go in another. She and the other take on Baugi and are impressed that Halfborn was able to take out the giant on his own, with Alex deheading him. They set sail and reach Jotunheim by morning.
The big banana gets stuck in ice and she turns into a walrus and pushes. They decide to walk to shore and huddle in groups to keep warm. She is paired with Magnus. When they are close to shore she kisses him. Skakdi arrives and invites them in to explain themselves. They wash up and have a meal with the giantess. She tells the Loki is near and he will launch Naglfar by midday the following day. She lets them stay the night and will send them away in the morning. She is woken up in the morning and after breakfast they get ready to ski over to Naglfar.
They arrive and she and Sam go with Magnus while everyone else creates a diversion. Magnus turns them invisible with the Othela rune Hearth gave him and they move forward. She hears the voices of her grandfather and Adrian, a friend of hers who committed suicide. The three arrive at the ship and board. After the distraction goes of the set out to find Loki. When the rune wears off she uses her shape shifting to fight the enemy hoards with Sam. Loki then appears and declines Magnus's offer to flyt. After her mother grudgingly accepts she and Sam go over to their friends and watch Magnus flyt the trickster. She is concerned and angry that he will lose. Alex is startled by Magnus's complement towards her about all her good deeds and blocks her mother's escape while Mallory imprisons him. They make a break and fend of the enemy forces and jump off the ship at Sam's request. They land on the backs of water horses and ride away just as the harbor freezes over.
They spend three days at sea, during that time she is taught by Blitz how to make chain mail clothing. She tells Magnus she was startled by his revelation about their kiss outside Skadi's fortress and needs her space. The Big Banana takes them to Vigridr, where they will die during Ragnarok, and are greeted by the gods. She is welcomed back by Sif and they go to the feasting tent and have a meal while they hand over Loki. They are given autographed copes of Odin's autobiography, a feast in their honor and Turkish bathrobes. They arrive back at Valhalla and Alex, now male, goes with Sam and Amir to dinner with their families. He returns to the hotel and goes to Magnus's room. He kisses the son of Frey and tells him he is on board with his idea.
After Magnus turns his ancestral home into a shelter for homeless youths, she helps him manage the place. During the Fourth of July, Alex, now female, and Magnus hold hands and watch the fire works while they value the present.
Alex is a teenage einherji, and shares a lot of physical traits with her mother Loki. She is petite, as stated in the Hammer of Thor, with sharp and beautiful facial features and the same sly grin as the god of lies. She has heterochromia, with one dark brown and one pale amber eye, and her hair is dark at the roots but dyed green. She also has a tiny symbol of Loki tattooed on her nape. Magnus noted that Alex's physical appearance did not change when she was a boy, except for her hair, which actually seemed to be longer.
Alex dresses rather flashily and flamboyantly, in primarily pink and green. He wears a pink-and-green argyle sweater-vest over a white tee, skinny lime green jeans, and battered rose high-tops. Tied around his waist like a kilt is a cashmere sweater, which conceals a garrote wire and a hunting knife tucked behind a belt. His appearance has been compared to both a jester's motley and a venomous animal giving off warning signs.
Alex Fierro is brave, sarcastic and moody, with a tendency to throw things at people when she is in a bad mood. Alex doesn't show what she feels readily, proven in the moment where Alex didn't want Magnus to heal him lest he saw into his brain.
Unlike Sam, who rarely shapeshifts, lest their father takes hold of her, Alex changes habitually, because she wants to make that power hers, not just Loki's so he can't use it to take hold of her. This defiance towards her mother is also shown when Alex tells Magnus that the tattoo that she has on her neck was originally a symbol of change and versatility, and that it later became a symbol for Loki. Alex liked the symbol and believed that it shouldn't just be Loki's. The tattoo is a sign of her defiance of Loki, not a sign that Alex is an agent of Loki's. The comfort she finds in pottery shows that she loves the idea of being able to change, just like her attitude changes easily towards Sif. Alex at first hates Sif; afterwards, when her opinion of her has changed, she decides to make a vase for Sif, and even keeps the wedding dress that Sif gives her.
Alex's bravery is shown throughout the Hammer of Thor. She defeats the blue wolf in the form of a German Shepherd, and gives a weapon to the Norse demigod in denial. Her plan to replace Samirah in the wedding is very courageous, and shows that she is willing to protect her friends, in this case, Samirah's promise to Amir.
- Pottery: In her room, Alex has a pottery wheel, which she uses to make clay vases. Each of her creations is branded with her initials and the symbol of Loki.
- Fashion Sense: Mallory Keen commended Alex on her choice of fashion, which included a dark green Stella McCartney dress and a tuxedo jacket.
- Camping Skills: Alex has spent many weekends with the kids at her pottery studio, camping in the woods as a way of getting away. These skills were displayed when she helped Magnus set up a fire pyramid and some pup tents.
- Shapeshifting: Just like her half-sister, Samirah, Alex has demonstrated her mother's ability to change forms. When she first arrived at Hotel Valhalla, she panicked and turned into a cheetah. When one of Odin's ravens captured her, she was a brown-and-white weasel. While saving a demigod in denial, moments before his death, he fought off the sons of Fenris as a German Shepherd. She also shapeshifted into Samirah when she was taken to Loki's cavern for her marriage with Thrym.
- Resistance to Loki's influence: As a side effect of using her shapeshifting powers so often, she is able to resist the power of her mother's influence on her body. As stated in in his room in Valhalla, he can do this is because he is comfortable changing; he has made his mother's power his own.
- Mystiokinesis: As a son/daughter of Loki, Alex can use magic.
- Enhanced Physical Abilities: After gaining a new einherji body, Alex's natural abilities greatly increased, making her stronger, faster, more durable and more agile than she originally was.
- Einherji Immortality: While within Hotel Valhalla, Alex, like any of the einherjar, cannot die, and will simply keep resurrecting from mortal wounds.
- Enchanted Garrote Wire: Alex uses her garrote wire, which she created after Loki taught her a spell, and uses it as her primary weapon.
Mr. Fierro and Stepmother
Alex was born out of an affair between her father and Loki. After Loki opened their eyes to the nine worlds they were never the same again. Alex was harassed by her father for Loki's deeds and for being gender fluid. This resulted in Alex being forced out onto the streets.
Her stepmother did not interfere while her father abused her.
Loki, the God of Mischief, is Alex's biological mother. He has made numerous attempts to take his life throughout Hammer of Thor. When he recognized Alex during Valhalla's battle training, he tried to kill him by causing Magnus to self-detonate by channeling his energy through him. Upon escaping, Loki willed Alex to die. This attempt however failed.
Alex and Sam have an unstable relationship. When they first met, Alex punched Sam in the face. They appear to cooperate well together during the wedding, but after the quest Sam upsets Alex by rejecting her offer to help the Valkyrie resist Loki's control over her.
By the time the set sail to stop their parent, the two have grown closer.
A Mexican sculptor who accepted Alex's genderfluid identity and was interested in reclaiming his Native culture. He did not get along well with his son, Alex's father, Mr. Fierro.
When they first met, Alex (as a cheetah) ran over Magnus' feet trying to escape the hotel and later decapitated him on the battlefield when he was about to "go nuclear." Magnus was initially confused when he learnt she was gender fluid, but throughout the book the two become more comfortable with each other. They have many things in common - both of them have a sarcastic attitude, both were homeless at some point in time and they both come from rich families which they chose to leave and ignore. Magnus was also the least doubtful of Alex's motives when she arrived in Valhalla. By the end of The Hammer of Thor, they are close friends.
Magnus also seems to have a crush on Alex, although he refuses to admit it. He is frequently caught staring at her, even gaping when he sees her in a wedding dress courtesy of Sif, and when she smiles at him in Randolph's mansion he mentions that he suddenly feels very warm. It is known that Alex likes him back, as she kissed him and holds his hand at the end of The Ship of the Dead.
At first, Hearthstone and Blitzen didn't know what to make of her and were doubtful, but they came around and became friends by the end. She learns how to "speak" ASL, so she can understand when Hearthstone signs. Both of them considered her brave for volunteering to replace Sam at the wedding.
When he first arrived at Valhalla, Alex was chased by Thomas Jefferson Jr., Halfborn Gunderson and Mallory Keen when he destroyed the hall. They are surprised that Alex stated she was female when they thought she was male. However after a few month of living together they have grown to think of the child of Loki as a close friend and comrade and vice versa.
- Alex is a gender neutral name - fitting, as Alex is gender fluid. The name comes from Greek "Alexandros", which means "protector of mankind."
- Fierro is Spanish for "iron."
- Alex's gender fluidity is most likely a reference to Loki's shape-shifting abilities and his two feminine forms – a mare that has become a mother of Sleipnir, and an elderly woman called Thokk who was responsible Hel not resurrecting Balder.
- Alex is female most of the time but occasionally has "very male days”.
- Alex is the third canon LGBT demigod (after Nico di Angelo and Will Solace) to be introduced in one of Riordan's series, as well as the first confirmed LGBT Norse demigod.
- Alex is the second known demigod of Mexican descent, the first is Leo Valdez.