The assault on Elsa's ice palace began as a mission mounted by Prince Hans and a group of Arendelle castle guards to find Princess Anna. It escalated into armed conflict after the group attracted the attention of Elsa's guard, Marshmallow.
When Kjekk returned from the mountains without Anna, Hans called for a group of volunteers to venture out to find her. The Duke of Weselton also offered up his two bodyguards, though he secretly gave them instructions to kill Elsa in an attempt to end her winter.
Ambushed by Marshmallow
Hans and his volunteers made their way to the North Mountain, where they caught sight of Elsa's ice palace. As the group approached the palace, Hans reminded them of their mission to find Anna and ordered them not to harm Elsa. However, the group was ambushed by Marshmallow, who had disguised himself as a pile of innocuous snow. Hans drew his sword, and the castle guards and the Duke's men used projectiles against Marshmallow, causing him to become aggravated and retaliate against his opponents, swatting the Duke's men into a mound of snow.
As the men recovered, they caught sight of Elsa at her palace's doors. While Marshmallow was preoccupied with Hans and the rest of the men, the two slipped past the snowman and charged up the staircase into the palace. Elsa fled from the Duke's men up to the top floor of the palace, but they pursued her and managed to corner her. One of the Duke's men fired a bolt at Elsa, but the queen was able to stop the arrow with a wall of ice. While the Duke's men tried to get another opening, Elsa began to fight back with her magic, preventing the men from firing a proper shot.
Concurrently, Marshmallow had managed to knock Hans to the ground and attempted to crush the prince. However, Hans was able to avoid the blows and used his sword to sever the snowman's leg. With Marshmallow crippled, Hans gestured to the guards and began to race up the staircase. Without his leg, Marshmallow lost his balance and began to fall into a chasm, but he made an attempt to bring Hans down as well. Ultimately, Hans was able to grasp onto a railing and was helped up by a couple of castle guards.
Elsa's last stand
With the Duke's men persistent on killing her, Elsa realized that she had to respond more aggressively; she struck out at one of the Duke's men, trapping him against the wall with ice spikes. Turning to the other guard, Elsa disarmed him, after which she trapped him and created an ice wall to push him through the doors leading out to the balcony. As the queen readied to kill the men, Hans and the guards entered the room, and the prince was able to calm her down. However, the bodyguard trapped against the wall used this opportunity to fire at Elsa. Hans caught sight of the movement and ran over to disrupt the bodyguard's aim, causing the arrow to shoot upwards and strike the ice chandelier hanging above Elsa. As the chandelier began its descent, Elsa ran to avoid being crushed, though the impact caused her to slip and lose consciousness.
With Elsa incapacitated, she was brought back to Arendelle and imprisoned in the dungeon. As a precautionary measure against her magic, Elsa's hands were immobilized by a set of metal gauntlets chained to the center of the cell.