"I'll ask you the question that haunts me. If you could go back, knowing what you know, would you have given them the car to have her alive?"
- Viper
"The Divine Beasts. The Guardians. It was… Calamity Ganon. It turned them all against us! And everyone—Mipha, Urbosa, Revali, Daruk. They're all trapped inside those things. All my friends, the entire kingdom, my father most of all… I tried, and I failed them all. I've left them all… to die."
Zelda's words haunted Link's memory, but they also filled him with a strange sense of lingering hope. They were all he thought about as he traveled deep into the Lost Woods, deep into the home of the Great Deku Tree, returning to the secret pedestal Zelda had used to seal the Master Sword for an entire century.
Even he couldn't explain what made him think it might work. Maybe he had absentmindedly read something in one of Zelda's massive research tomes in the days leading up to the Great Calamity and it had just jostled back into his mind. Maybe some latent voice silently calling out from the Sword itself was drawing him back. Maybe it was those odd dreams he had been having of a skeletal master swordsman trapped in a cloudy void telling him, "Hey, kid, just manage it the way I used to."
Finally he found the clearing. The Great Deku Tree was asleep. The Kokiri were somewhere hiding in the trees, as they usually were. The pedestal was vacantly waiting for him.
Link lifted the Sword over his head, took a long breath, and thrust the silver blade into the raised fissure.
The platform began to glow in a ring under his feet. A cylinder of bright blue light rose up around him and continued several hundred yards into the sky. The trees around him lost their leaves, covered in snow, and regrew their foliage thousands and thousands of times… in reverse. The blue light faded around him when time returned to its natural flow.
Link let go of the Master Sword's pommel and instinctively turned around. Zelda was standing there just behind him, with a face that said she was shocked to see him suddenly appear before her at full health. She was looked exactly like she did 100 years ago, at the exact moment she had placed the Master Sword in the pedestal so Link could recover it in the future.
"Link…?" the princess whispered in disbelief.
He stepped down from the pedestal, silent but determined. He left his scabbard empty.
"What are you thinking, Link?!" Zelda gasped. "You need the Master Sword to face Calamity Ganon!"
"It stays here. I'll find plenty of replacements," Link finally spoke. The path he was about to take would make the battle infinitely more grueling for himself, but it could also prevent so much misery for the others.
"I have to keep the loop closed," he said simply.
Zelda blinked in confusion. Link softened his voice to help her through her fog.
"When we were retreating, you said we left our friends to die, right? Well now you've got your powers to work, and I don't need to waste a hundred years in the Chamber of Resurrection. We're going back so they don't have to die."
"Link, I don't even know what I was thinking when I said that!" Zelda cried out. She always tried to be the optimist, but she was also a realist. "You were wounded hours ago! We were running the whole night before that! It's been a full day since this disaster started! They're probably already-…"
"Then I guess we'll have to find out for sure," Link interrupted, not letting those darker possibilities dim his resolve.
"The Divine Beasts are going on a rampage," Zelda said nervously. "Castle Town is burning. My father's men must be holding out in the Temple of Time, if they're not already… Where do we even head for first?"
"We're starting with Ruta," he said as if he meant to defy fate herself.
Zelda froze in thought for a moment, then nodded. Together they departed the Lost Woods and rode straight back into the heart of the Calamity.
Author's notes: I'm not sure if this loophole exists in the Japanese version of the dialogue, but I'm rolling with it.