On one of the tallest mountains in the Digital World was a lone figure sitting on the cliff side in deep mediation.

The Digimon was none other than the hero of Shinbuya and bearer of the Digital Hazard, Guilmon.

However, he looked completely different.

Guilmon had been training in a room that gave him training of 7 years in just 3 days.

He was now much taller than before as the muscles in his legs stretched out, giving him a better height advantage.

Guilmon's arms, legs and chest were far muscular and developed.

Bandages had been wrapped around his arms, as a brown scarf adorned around his neck, the end of the scarf blowing in the wind.

And the goofiness he had when he was a child was now gone as his mind and body were now more mature and serious.

But upon meditating, Guilmon started to have terrible flashbacks.

He remembered digging around in some cave when he was young and found a small room with a mysterious scroll and an old chest.

Unable to contain his curiosity, Guilmon opened the chest, even though it was sealed and had clear warnings not to, that released a dark purple aura, in which some of it entered his body without him even noticing.

Taking the scroll, which unknown to him was a key to save the world, he entered the tournament and met many good friends in his fights such as Biyomon, Agumon, Dorulumon, Veemon, Gatomon and Shoutmon, easily defeating Impmon there along the way, who was sore about losing but got over it as Impmon soon realized their friendship was more important than some title.

However, after he freed Gallantmon from the Virus that had corrupted him, it turned out the dark aura is the Virus and with the tournament over, Guilmon soon felt the effects of the Virus slowly take over him, but it was too late as his mind was corrupted and he was transformed into a dark version of himself.

His skin turned black, while his stripes and patterns became dark.

His eyes went from their usual kind and innocent filled yellow to a complete red, as they did when he underwent a Dark Digivolution and turned to Megidramon.

And lastly, he wore dark armour with a living eye on it and a helmet.

Guilmon was no more, now there was BlackGuilmon.

As BlackGuilmon, he went on a rampage, destroying many Digimon's lives and taking their Data to make himself stronger, if it weren't for Agumon who clawed at his armour eye.

Guilmon would've remained in his state of pure evil but retained his mind and memories back, in which he tore off the armour and helmet, turning him back to his old self once more and then slashed right his claw into the eye, ending his nightmare once and for all.

But...

The memories he did as BlackGuilmon still haunted him to this very day as he finally opened his eyes and panted and began to sweat and knew he couldn't see his friends again after all the misery and pain he caused.

After freeing himself of the Virus' control, Guilmon went alone to a special room where he could get years of training in just a few days.

The training was hard, long and intense as he pushed himself to his limit and beyond, also gaining more knowledge on many things and also improved his speech.

Guilmon's training featured lots of weight lifting, push-ups, learning to control and increase the power of his attacks, special arts training and many more training exercises.

Plus, the room had a gravity of 1000, so getting through it was hard but it was worth it so he would not fall under the evil control ever again.

He couldn't bare to show his face to everyone gain, not even Agumon, Veemon, Shoutmon, Dorulumon, Gabumon, Biyomon, Gatomon, Impmon, Wormmon, Patamon, Gomamon. Tentomon and especially Terriermon and Renamon again, not after all the crimes he committed while as BlackGuilmon.

Only Agumon, Veemon and Impmon knew that Guilmon was BlackGuilmon and they were shocked when they saw him overcome his darker side before the bearer of the Digital Hazard then ran away from them afterwards.

Breaking from the horrid memories of his past, Guilmon was about to go back in mid thought again when a dark voice said. "Guilmon..."

Guilmon turned around and was shocked to see BlackGuilmon standing before him.

He too got a muscular figure but still wore the same armour and helmet when he had taken over Guilmon.

"Did you really think you could rid me so easily?" BlackGuilmon asked slyly.

Shocked, Guilmon demanded his dark alter ego. "How did you come back?"

"The Virus can regenerate any time it likes." BlackGuilmon replied, before stating "It might've taken me three days to get myself back into my prime form but my body is now taken up the same form you now have. And I'm going to finish what you started for me. Destroy the Digital World!"

"Never! I created you, I can destroy you!" Guilmon snarled back, ready to strike BlackGuilmon down.

"But the main question is can you be trusted again?" BlackGuilmon cackled.

"I won't allow anyone else to be involved. I hunt you down alone!" Guilmon replied in a determined tone, which only seemed to amuse BlackGuilmon.

"Alone? I think not. But you're welcome to try." BlackGuilmon laughed before disappearing again.

Guilmon knew that was no illusion.

Somehow his nightmare had returned, making the red dragon Digimon clench his hand into his fist and think out loud. "No more Data will be lost and nobody will be harmed ever again. I can promise you that."

Guilmon then left the Cliffside to go on a journey for amendments to his sins.

He wouldn't rest until BlackGuilmon was destroyed for good, unaware the whole time he and BlackGuilmon had been watched by Patamon, who saw the whole thing.

"So now they're separate? This is bad. Guilmon needs help. I must tell the others!" Patamon stated in a worried tone, before the Digimon of Hope darted back to the others as fast as he could.