The Legend of Yin and Yang

A Quick Flashback

Wither had met Zale some time during the Great War between the Corruption and the Hallow. That day, Wither had gotten closer to death than ever before.
He was five on that day, young enough to know his enemy, but not old enough to know how to defend himself.
He was cornered by three Unicorns. They were readied to charge in on him on the slightest move.
Wither was scared out of his mind. He had no weaponry, no armor - nothing.
Something caught his eye - a Corruption Elite, flying over with a Jetpack.
Two of the Unicorns changed their focus on the Elite, while the other one kept Wither cornered, and unable to do anything.
The Elite made quick work of the two Unicorns that went after him, and then slaughtered the final one.
Wither, who had been scared out of his mind from the encounter, stared the Elite in the eyes.
"C'mon, kid," he had said to him, "I'm getting you back to the Corruption!"
As he spoke, they were slowly being surrounded by Gastropods.
Wither did not recognize the Gastropods, but he knew that they weren't on his side.
The Elite took notice of this, grabbed Wither, and flew up, heading back towards the Corruption.
The Gastropods opened fire on the two, leaving the Elite to dodge as well as he could.
Wither was hit in the chest with one of the shots.
A few hours later, they had finally reached the Corruption. The Elite dropped Wither down onto the ground, forcing him to try to land perfectly. Of course, Wither never had experience in landing like this, and rolled on the ground for a few feet.
The Elite landed next to him, seemingly worried.
Wither slowly got up, trying not to hurt himself any more than needed.
"My name is Zale," the Elite said to him.
Wither simply nodded - he didn't know what to do right now. He was confused, lost, and angry.
"C'mon, let's get ya some proper armor." Zale led Wither to one of the chasms, and jumped down, leaving Wither to figure out how to get down on his own.
Wither landed inside the tunnel of the Corruption, being hurt pretty badly.
Zale, who had been standing there, dumped a Healing Potion on Wither.
"Ya gotta be more careful, kid," Zale warned. "If the fall doesn't kill ya, whatever ya land on will."
Wither stood up, trying to keep his balance (the fall disorientated him a bit).
"Alright," Zale continued, "it's about time to get ya some proper armor."
Zale pulled a lever that was on the floor, revealing a room filled with different armors.
"Alright, go ahead and pick out one ya like," Zale said, before pushing Wither into the room, and closing it.
Wither looked around at the many armors, some of which he recognized - Meteor, Iron, Platinum. Some of them he had never seen before, like an armor set that kinda looked like a beetle, and another one made up of some kind of blue metal.
That's when he saw the armor he wanted - Shadow Armor.
The door opened up.
"Did ya find one yet?" Zale asked, seemingly impatient.
Wither pointed at the Shadow Armor.
"The Shadow Armor? You sure?"
Wither nodded.
"Well, it's your funeral."
Zale did some strange reality bending, causing the Shadow Armor to suddenly be worn by Wither.
"I was kinda thinking you would've gone for the Beetle Armor, but I guess idolizing the Corruption is acceptable."
For many years after, Wither and Zale fought off hordes of Hallow and Crimson enemies together, with Wither growing stronger after every battle, stronger than Zale ever could've imagined. When they weren't fighting, Zale was training Wither.
Wither hoped this friendship would never end.
But, as he's learned from the death of his parents, nothing lasts forever...