Sidon

Prince Sidon is a playable character in Hyrule Warriors: Age of Calamity. Zora King Dorephan's younger child and Zora Princess Mipha's younger brother, his older self from 100 years into the future in Breath of the Wild is summoned back to during the Great Calamity to save his sister from Waterblight Ganon and keep Divine Beast Vah Ruta in Hyrulean control.

Role In Game
Sidon's younger self is first seen trying to fight the hulking red-maned Lynel that lives on Ploymus Mountain near Zora's Domain. After Link, Zelda, Impa, and Mipha arrive and scare it off, Mipha voices how worried she was for Sidon, but then voices how proud she is of Sidon's bravery, causing Sidon to flash his trademark toothy grin and salute to his big sister.

Later on, during the Great Calamity, as Mipha faces off with Waterblight Ganon inside Vah Ruta, she realizes she is outclassed and outmatched by the Shard of Calamity Ganon and prepares to face her death with dignity. Just as Waterblight Ganon moves in for the kill and flings its water-born flail arm at Mipha alongside its Cryosis constructs, the older Sidon arrives through a time portal and deflects Waterblight Ganon's strikes, refusing to lose his sister a second time to the monster. Mipha is shocked seeing Sidon older and all grown up, but nevertheless, even with his help, Waterblight Ganon seems too powerful. As she attempts to attack it again, despite Sidon's pleas, thankfully, she doesn't need to as Link arrives, and together, the three of them are able to destroy Waterblight Ganon, keeping Vah Ruta under their control and out of Ganon's clutches. Sidon then goes on ahead to clear the way to Vah Rudania, taking out the Talus that was reinforcing the lava guarding Vah Rudania, allowing Link inside to aid Daruk and Yunobo against Fireblight Ganon. With Fireblight Ganon destroyed and Vah Rudania safe, Mipha is given a chance to talk to Sidon about if it really is her little brother, all grown up. Once Sidon assures her it is him, flashing his trademark toothy grin and salute, he explains that he came from the future to help. Daruk initially laughs it off, reminding everyone they have more important business to deal with regarding Calamity Ganon, but later on, as Zelda recalls what happened, Sidon explained that he heard a voice, saw Mipha struggling, and before he knew it, he was inside Vah Ruta protecting her.

Sidon continues to aid Link, Zelda, and the other Champions alongside his sister Mipha with defending Akkala Citadel from the onslaught of Ganon's forces of monsters and corrupted Guardians, using Vah Ruta to take out massive waves of them to take some pressure off the Citadel's defenses, before then moving to aid Fort Hateno and clearing Hyrule Field of massive numbers of Ganon's monsters and Malice-infused Guardians. Once summoned by Purah to join the united allied coalition of the various races around Hyrule, Sidon and Mipha are more than ready to help, and with Zelda leading the assault, they lay siege to Hyrule Castle to take it back from Calamity Ganon.

Sidon aids in fighting past some of Ganon's most elite troops he had left, but upon confronting Astor and Harbinger Ganon, it is not long before, upon being defeated, Astor tries to order Calamity Ganon to consume the heroes, but is consumed instead to allow the Harbinger Ganon to become a perfected physical body for Calamity Ganon. After Link is forced to attack Terrako, the small Guardian that brought Sidon back in the first place, after it was corrupted by Malice from Calamity Ganon, critically damaging it, Sidon mourns for Terrako before Zelda, her resolve strengthened by fury and vengeance for Terrako, leads them to face Calamity Ganon in the castle citadel. However, Calamity Ganon's perfected body proves invulnerable to any of their attacks, until Terrako, despite its condition, heroically throws itself at Calamity Ganon and self-destructs, breaking Calamity Ganon's defenses and rendering it vulnerable to attack. Once Calamity Ganon is weakened enough, Link delivers the finisher with the Master Sword, cleaving Calamity Ganon in half, allowing Zelda to finish it off with her awoken sealing magic, banishing Calamity Ganon back into his slumber once more, winning the war in Hyrule's favor.

As everyone gathers out on the castle balcony to celebrate their victory, the ancient screw that Zelda recovered from Terrako suddenly glows, as do Sidon, Riju, Teba, and Yunobo. With their mission completed, and Hyrule of an alternate timeline safe from Calamity Ganon, with the Champions still alive, it was time for the future Champions to return to their own timeline. Mipha exchanges her final goodbyes with her older, but still younger brother, who promises to remember their time together, knowing that, while he was returning to a timeline that she died in, he made a difference in saving her in an alternate timeline so that the Sidon of that alternate timeline can grow up with his sister still there to comfort and help him. With their goodbyes exchanged, the future Champions are returned to the Breath of the Wild timeline.

Quotes
"NO! I will not allow you to take her again!"