Queen Elsa is one of the main antagonists of Disney's "Frozen", along with Prince Hans and The Duke of Weselton. While Elsa is a generally heroic person with heroic intent, she goes to villainous extents to achieve them. Such as sending a snow monster after Anna so that she can protect her. Elsa is an antagonist hero and anti-hero.
At a young age, Elsa realized that she holds an ancient ability over ice and snow, and often used her abilities to play with her younger sister, Anna. Elsa shared a close bond with her free-spirited younger sibling, and the two were the best of friends. However one night while the two were playing in the ballroom, Anna falls too high from the snow slopes Elsa had created. Elsa tries to save her by using her magic, but accidentally strikes her sister instead. Their parents, The King and Queen, immediately seek aid for Anna by visiting the legendary trolls, whose leader, a shaman named Pabbie, is able to stabilize Anna's condition since it had only affected the head, not the heart, which would have been fatal. To be safe, Pabbie then removes Anna's knowledge and memories of magic, much to Elsa's despair. Pabbie takes the time to explain the true strength of Elsa's abilities, telling her there's not only beauty in it, but danger, and that she must learn to control them at all cost, or fear will be her enemy. While the King promises to help Elsa control her powers, the incident leaves Elsa traumatized by them. As a result, the King and Queen order the gates to be locked for Elsa and Anna's safety. From then on, Elsa forcibly spent the rest of her life distanced from the kingdom, including Anna, trying to keep her powers from growing out of control and harming those she cares about. Even so, the persistent Anna tried time and time again to spend some quality time with her sister, but failed at every turn, leading her to eventually believe Elsa despised her.
Throughout the years, Elsa's only true human contact was with her parents, who calmly helped their daughter control her abilities, teaching her to remain calm for fear and stress would only cause chaos. To help further, the king bestowed upon Elsa a pair of gloves, which were able to suppress her powers (teaching her to conceal, don't feel, don't let them know), making life much easier, though still heavily fearful. And despite better control, Elsa still refused to contact Anna, truly terrified of harming her yet again. One day, during Anna and Elsa's teenage years, the king and queen left for a trip, and though Elsa was torn about their parting, she bid them farewell as they were off. However, this would be her last time with them, as the royals would die at sea during a powerful storm. A funeral was held, though Anna was the only one of the sisters to attend. Elsa, instead, stayed within her bedroom, mourning for the loss of her parents, alone. Because of her devastated emotions, her powers corrupted the bedroom, freezing everything inside and reflecting the sorrow of the event. With the passing of her beloved parents and contact with Anna still deemed too dangerous, Elsa was now truly alone.
Three years later, Elsa is chosen to be crowned the new queen (regnant, not consort). Elsa, though reluctant to remove her gloves to take the royal orb and scepter, is able to control her powers and is crowned. Later, however, during the ball, the Duke of Weselton tries to dance with Elsa, but she gets Anna to briefly join him. While he makes a fool of himself with his silly dancing, Elsa gets to exchange some words with Anna for the first time in years, but as Anna goes to tell Elsa how they'll get to spend more time together again, Elsa states it will not happen. As Elsa spends her time during the party, Anna arrives with Prince Hans to ask for her blessing in their upcoming marriage. Elsa is startled, and refuses over the fact that the two had just met and Anna's misunderstood the idea of true love. While Anna retaliates by asking why Elsa keeps shutting her out, Elsa starts to walk away, so Anna grabs at her, pulling off her glove. As Anna still pleads with her to tell her why she is behaving this way, Elsa accidentally exposes her abilities to the citizens by creating a wave of ice-picks. Elsa runs out of the castle before all the other excited subjects. Elsa's powers further reveal themselves, surprising and frightening everybody, with the Duke claiming her to be a monster inflicted with sorcery.
She runs all the way to the river with Anna chasing after her. As everything begins to freeze, Elsa runs over the water, and with every step she takes, she causes the entire body of water to turn to ice, trapping all the ships before spreading throughout the rest of the kingdom. Elsa then retreats to the northern mountain, accidentally placing a frozen curse on her kingdom as she leaves. At first, she's still dreadfully downhearted by all that's just happened, the pain of her past consuming her. However, oblivious to the storm she caused, she starts to embrace her powers now that she is alone, letting them roam free, happier than she's ever been in years. Now that she's living without fear of harming those she cares about, Elsa has ultimate control over her abilities and creates herself an ice castle and a gown out of her magic, establishing herself as the Snow Queen and officially abandoning her place as queen of Arendelle, declaring she's never returning to her kingdom now that she's finally happy and completely free. She also recreates Olaf, the snowman she built with Anna as a child, but unknowingly imbues him with life. With his new enchantment, Olaf heads off into the world, eventually stumbling upon Anna and leading her to Elsa's castle sometime afterwards.
From that day forth, Elsa lives peacefully in solitude, until one day when Anna enters her castle. While Elsa becomes slightly elated that Anna had come to visit her, she is still hesitant to return to Arendelle, as well as rekindle her bond with Anna, still fearful of harming her. Elsa then advises Anna to return home where she's safe, wanting her to be happy in Arendelle, but Anna refuses to do so just as Olaf rushes in, reminding Elsa of the whimsical childhood the sisters shared. It was enough to bring a smile to the queen's face until the memory of nearly killing Anna haunts her again, prompting Elsa to turn away, bidding farewell to her sister. Anna accidentally increases the discomfort and stress upon mentioning the kingdom's in danger, Elsa being horrified to learn that she had placed a curse upon it. Overcome by fear and guilt, Elsa unleashes her powers by accident once again, but this time, she inadvertently hits Anna in her heart. As Olaf and Kristoff (Anna's companion who offered to help guide her through the mountains to find Elsa) run to try and aid Anna, Elsa demands for them to leave her, as Anna belongs in Arendelle and she, however, does not. While Anna still insists she come back with them, telling her she won't leave any other way, Elsa is forced to create a gruesome snow beast known as Marshmallow, who throws the trio out of the castle.
Afterwards, Marshmallow becomes Elsa's official bodyguard, given that Elsa truly wants nothing more than to be alone, and disguises himself as snowy rocks outside of the castle to keep away any and all visitors who may harm her majesty in any way. Meanwhile, within the walls of the once beautiful ice castle, Elsa has shown to have, despite desperately trying to conceal her emotions, lost control over her powers once again, as the fear of endangering Arendelle has completely overcome her, causing ice shards to fill her castle, giving it a darker and fearful design, matching the monster Elsa fears she has become. Meanwhile, Anna becomes weak, with Kristoff correctly believing it's due to Elsa striking her. To find a cure, Kristoff leads Anna and their companions to the Valley of the Living Rocks, where Pabbie returns and informs them that unless Anna is able to perform an act of true love, Elsa's icy curse would eventually freeze her, killing her. To save herself, Anna and the others rush back to Arendelle to find and receive a kiss from Hans before it's too late, believing true love's kiss is the act that would break the spell.
Meanwhile, back in the mountains, Hans and a group of soldiers arrive to arrest Elsa after believing she had killed Anna. Marshmallow immediately leaps into action, and Elsa, upon hearing the commotion, flees inside and tries to hide. As Marshmallow defends against the attack, two soldiers sneak past him and enter, searching for Elsa in an attempt to kill her as per the Duke's orders. They soon corner her, and Elsa is fearful at first, but eventually uses her abilities and comes close to nearly killing the two, completely furious at the harm they've brought upon her and her home. Outside, Marshmallow continues to battle, but Hans brutally injures him and causes him to go plummeting into a chasm to his apparent death, leaving Elsa devoid of protection and allowing Hans and his henchmen access into the castle, where Elsa has gained the upper hand against the Duke's goons. Just as Elsa was about to murder the two, Hans appears and stops her, telling her not to prove she's the monster they believe she is. Elsa settles down a bit at Hans' words. However, one of the soldiers aims his arrow at Elsa, still following the Duke's orders, and just as he is about to shoot her, Hans intervenes, causing the arrow to cut through Elsa's chandelier which then plummets towards the ground. Elsa tries to escape the collision, but is knocked out in the process. Hans and the soldiers then capture her and head back to the kingdom.
Elsa soon awakens to find herself within the castle dungeon. Chained down in shackles, the snow queen finds herself trapped as she looks out the cell's only window, finally witnessing the disaster she's brought upon her former kingdom. Just then, Hans arrives to speak with her. Elsa asks for Anna's whereabouts, but Hans explains she hasn't returned, much to Elsa's concern. The prince then pleads for the queen to end the curse, telling her it'd make things better, but she regretfully denies, telling Hans that she's unable to. With that, Hans takes his leave, just before Elsa begs for freedom, to which Hans claims he'll do what he can. Once he's gone, Elsa's powers suddenly get the better of her chains and are able to destroy the cell, allowing her to escape. Elsa flees the castle and heads back into the fjords to return home, but her fearful emotions cause a deadly blizzard to consume Arendelle, making her escape that much more difficult, just as Hans learns of her escape. Needing to put an end to the winter, Hans heads out to kill Elsa, believing her death would not only free the kingdom, but earn him praise and admiration, selfishly wanting to rule the land as a beloved king.
Meanwhile, with Hans having betrayed Anna and revealing himself to be a ruthless murderer, her curse becomes stronger and her death process is nearly complete. Olaf, however, informs her that Kristoff is the one that truly loves her, and that he's the one she must kiss to save herself. Anna and Olaf retreat to find the mountain man, just as Hans confronts Elsa not too far away. Elsa pleads to be left alone, and asks Hans to take care of Anna for her, to which Hans responds by telling her about the curse she accidentally put upon Anna, and that she died from it despite his efforts to save her. Devastated by the heart wrenching news, Elsa collapses and mourns the death of her sister, ceasing the blizzard and giving Hans the chance to finally eliminate her, as she's now vulnerable. Hans slowly approaches the Snow Queen from behind and draws his sword, ready to decapitate her. However, Anna arrives on the scene, and although she was freezing to death quicker and quicker, she jumps in front of Elsa as her curse takes full effect, turning into an ice statue the second Hans' sword hits, causing him to fall back unconscious just before her last, dying breath is lost.
Elsa recovers and sees her sister's fate, causing her to weep and clutch on to the statue while blaming herself for bringing this upon her. However, Anna's saving Elsa was an act of true love, and thaws her frozen heart, while bringing Anna back to life. Elsa is overwhelmingly joyous at the turn of events, shocked by the fact that Anna risked her life to save her. Anna responds by telling Elsa she loves her, and Olaf explains the act of true love was Anna's sacrifice, and that's what thawed her heart. These words from the snowman give Elsa the realization that the curse can be lifted, and that love is the key to doing so. Realizing that love enables her to control her powers, Elsa is able to use this and focuses herself, removing the icy curse from Arendelle and bringing summer back to the kingdom. With peace restored, Elsa rekindles her bond with Anna and is praised by her people for freeing them from the curse, having learned she's far from a monster. Elsa then resumes her position as queen, uses her abilities to give Olaf an ice cloud to prevent him from melting, and creates a rink in the castle courtyard for the people of Arendelle to enjoy. Elsa declares they'll never close the castle gates again now that she's finally accepted and makes a pair of ice skates for Anna, the two sisters then joining the celebration of harmony, having the fun they used to share together at long last.