During their travels, Sacha and Pikachu discover the injured Keldeo atop a train. They rescue Keldeo, helping it escape Kyurem's pursuit by taking shelter inside the train and ensuring it receives medical treatment at Roshan City's Pokémon Center.

Learning Kyurem froze the Swords of Justice and Keldeo's desperate need to save them, Sacha pledges his support. He collaborates with Iris and Cilan on a rescue plan. Iris secures a museum zeppelin to create a diversion, while Cilan lures Kyurem and its Cryogonal minions away using a mine cart. This clears a path for Sacha and Keldeo to proceed on foot towards Kyurem's lair, the Full Court.

At the Full Court, Sacha directs Pikachu, Pignite, and Boldore to attack the ice encasing the Swords of Justice. This draws Kyurem's fury, leading to a near attack on Sacha before Keldeo intervenes. Sacha's presence and encouragement fortify Keldeo's resolve to face Kyurem again. During the climactic battle, Kyurem unleashes an attack accidentally aimed at Sacha and the group. Keldeo intercepts it using Secret Sword, shielding Sacha but suffering injury itself.

Sacha functions primarily in a supportive role, aiding Keldeo's mission rather than driving the central conflict. He embodies themes of friendship and perseverance, reinforcing Keldeo's determination to grow stronger. The rescued Swords of Justice acknowledge Sacha's crucial role in their freedom and Keldeo's development.