The Master Sword speaks to Zelda, informing her what she must do to save Link and Hyrule. After Zelda awakens her sealing power to save Link from a Guardian Stalker, Link collapses in exhaustion. During Link's 17th Recovered Memory, ' Zelda's Awakening', Link is greatly wounded and the Master Sword is in poor condition. In Link's third Recovered Memory, ' Resolve and Grief', Zelda asks Link if he can hear the master sword speaking to him. In Link's first Recovered Memory, ' Subdued Ceremony', the royal speech the Princess Zelda recites states that the sword is bound to the Hero of Hyrule and will always aide him whether he is 'skyward bound', adrift in time, of steeped in the glowing embers of twilight. The sword was again wielded by Link, who used it in a ferocious battle against Ganon, who broke free from his prison to cause total destruction to Hyrule. Link is told by Impa that ten-thousand year prior to the events of Breath of the Wild, a hero used the sword to seal away Calamity Ganon within Hyrule Castle.

This may be a choice from the Goddess, Fi, who sleeps eternally within the sword and will only assist her heroic master. The sword will only accept its master by its own will, and will choose a hero that has gone through great trials and the test their courage, power and wisdom to prove him worthy of wielding it. The sword is considered the only weapon that has the power to defeat Ganon in the games that it appears in. Din's Flame is imbued in the sword, which has the Power to Repel Evil, a power augmented after the sword received a blessing of Zelda, which then transformed the blade into the True Master Sword. The sword was originally crafted by the Goddess Hylia as the Goddess Sword, which was forged in the Master Sword by the Goddess' chosen hero and it's spirit, Fi, who bathed the blade in three Sacred Flames located across the land that would later become Hyrule. First appearing in The Legend of Zelda: A Link to The Past, it has become a predominate feature to the series, appearing in almost every game, in logos, all alongside the Hylian Shield. The Master Sword, also known as The Blade of Evil's Bane, the Legendary Sword, the Master Sword of Resurrection, and the Sword that Seals Evil, is a recurring weapon that appears in The Legend of Zelda series. Only a hero chosen by the sword itself may wield it.' Its blade gleams with a sacred luster that can oppose the Calamity. 'The legendary sword that seals the darkness.

A light in the forest wiki