Darkness and Light, into the chaos.

Andrew came to the living room where Derpy sat. "Hey." he said.

"Hey." she replied. "So what's the plan?"

"Naraku will probably use fiend monsters, so I need to prepare for that." Andrew said, then noticed the look on Derpy's face. "What's wrong?" he asked.

"Nothing." she replied, turning away.

"Derpy, I've known you for almost sixteen years, I've seen all your emotions, something's wrong, now spill." Andrew said.

"I can't shake the feeling I get from Osiris' accusations. That his burns were all my fault." After a confused look from her husband, she continued. "Osiris is my brother, we used to do everything together until one day when we were playing a little too close to the heat generator."

I think I know where this is going. Andrew thought, wrapping his wing around his teary-eyed wife. "And you misjudged the distance and knocked him into the generator, right?" Derpy nodded silently before bursting into tears. "There's no way that's your fault. Derps, you couldn't control what happened. Osiris knew it and he shouldn't have gone along in the first place." he said, gently stroking her mane. Andrew forgot about preparing for his duel and just sat there with Derpy, letting her cry on his shoulder.

...

A few hours later, night came and so did Naraku. Andrew and Derpy stood and studied the sky as the rest stood by. "There!" Andrew called, pointing to the spider in the sky. Those with wings or levitation began their accent (The earth ponies had to catch a ride with their monsters). A floating Castle came into view as they neared the mark. "That's Naraku's first castle." Andrew muttered.

"Incoming!" Destiny called as millions of shadow creatures and the odd changeling came straight for them.

"Hit 'em fast, hit 'em hard. Night King Transformation!" Andrew called, slashing with his claws at anything that got near him. The other ponies called theirmonsters and ordered attacks. "Ray Pulse!" Andrew snapped, an orange energy beam coming from his outstretched hand. With in seconds the enemies were cleared and the ponies touched down in the courtyard.

"Welcome." Naraku said as he appeared from the shadows. "My associate and I are ready for our duel."

"Associate?" Stream asked as he saw a pitch black pony rise in front of the group.

"You may call me Shade." she hissed.

"Well I wasn't expecting this." Andrew admitted, calling his disk.

"I was. Shadow Guard Transformation! Dark shield disk, engaged!" Destiny stood next to her father. "I'll be your partner this time." she said with a grin.

"Duel!"

Andrew & Destiny:8000

Naraku and Shade:8000

"I'll kick things off." Destiny said, drawing. "I'll start with the Field Spell, Soul Arena-Lost Citadel!" The scene changed instantly and they were standing in the all too familiar Citadel. "Now all monsters with 'soul' in their name get a 500 point boost. I summon Soulborn Noble-Raphael(ATK:1800-2300). I play two cards facedown and end my turn."

"My move," Shade hissed, "I summon Brron Mad King of Dark World(ATK:1800). Then I play Dark World Lightning to destroy the facedown you played." the card exploded. "I end my turn by finishing the effect of my spell and discarding a card."

"My move then." Naraku smiled. "I summon this in defense mode and that's all."

"My move." Andrew said. "I summon Chthonian Soldier(ATK:1200), then play three cards facedown and call it a turn."

"My draw. I summon Guardian Eatos(ATK:2500), then play Gravity Ax Grarl to summon Guardian Grarl(ARK:2500-3000). I'll then play from my hand Soul Caster-Kama. Now I can play a spell card in my graveyard, and I choose the one Shade destroyed, Infernal Soul. Now I can summon one Soulborn from my deck with a level less than or equal to my strongest monster. I choose Soulborn Mimic-Charade(ATK:2300-2800), and now that he's on the field, I can summon Soulborn Demon-Inferno from my deck(ATK:3000-3500). I overlay level * Eatos, Grarl, Charade, and Inferno." the four monsters turned to streams of light and the dark pillar erupted from the overlay network. "Let the darkness in my heart fuel your strength. I summon Nightmare the Soul Edge Vessel(ATK:5000-5500)!" Nightmare stood at his partner's side.

"Now for the fun part." Andrew smiled.

"That's right. Nightmare gains 200 attack points for every, and I do mean every, dark monster on the field. There are five, which means Nightmare gains 1000 attack points(ATK:5500-6500). Soul Edge Strike!" Nightmare brought his blade down on Brron.

Naraku & Shade:8000-3300

"Nightmare looses a few points(ATK:6500-6300), but I'm not done yet. Raphael, direct attack!"

Naraku and Shade:3300-1000

"I'm done."

"Draw." Shade looked at her hoof. "I think I'll switch tactics. I play Infernity Reckless Summon to summon my remaining Brrons and play Monster Reborn to bring back the first one, then I sacrifice them all to summon The Winged Dragon of Ra(ATK:5400)" Ra let out a screech. "now Ra, attack Chthonian Soldier."

"I play my Trap. Negate attack!" Naraku snapped. "Now the battle phase ends."

"I end my turn." Shade grumbled, realizing her mistake.

"My move. I sacrifice my facedown Monster to summon Vanity's Fiend(DEF:1200). Nightmare gets a boost(ATK:6300-6500), but now you can't special summon. I end my turn with two cards facedown."

"My move, I draw." Andrew looked at his hand. Okay, if I summon Sangan, I could get another monster in my hand, and I can't use my Rabbit's effect, so here goes something. "I play this in defense mode and end my turn."

"My move. Nightmare-"

"I play Fiend Sanctuary. Now no monsters can be targeted for an attack as long as I have a Fiend on my field.(Yes, I made that up)"

"I end my turn."

"My move, Due to my partner's trap, I'll pas this turn." Shade hissed.

"My draw. I summon Trance Archfiend and play Double Summon to sacrifice my monsters to summon Earthbound Immortal Uru(ATK:3000). Direct attack." Uru bit down on Andrew.

Andrew & Destiny:8000-5000

"I end my turn."

"Not good." Andrew huffed, drawing his card. "This duel is over. Without your Fiend in play, I can summon Rescue Rabbit and use his effect to summon my Shining Angels(ATK:1400 x2) then I overlay them to summon Starliege Paladynamo(ATK:2000) Now by discarding two overlay units, I can reduce your monster's points to 0 and negate his effects. Say goodbye to Uru(ATK:3000-0). Starliege attack! Go Star Saber Slash!" the shining warrior slashed the giant spider right down the middle. "We Win."

Naraku & Shade:1000

"What?" he asked, then saw a puff ball. "You had a Kuriboh." Andrew said with obvious annoyance.

"That's right, and I'm playing Call of the haunted to resummon Uru(ATK:3000)."

"I end my turn."

"My move." Okay, they have an Earthbound Immortal, an Egyptian God Card, and five facedowns between them. I have Nightmare and Raphael with two facedowns of my own. Dad has three monsters and facedowns. We can't attack Uru, I have no way of destroying him otherwise, and it'll be over one way or another in this round. Let's see what we've got. Destiny drew her card. "I summon Soulborn Seeker-Talim and with her ability I can overlay her with the Voldo in my hand to Xyz summon Soulborn Orphan Amy(ATK:1500-2000)." her entire body began glowing with a purple aura. "This duel ends now. I tune Nightmare and Amy together. Go Xyz-Synchro!"

"Xyz-Synchro?" Naraku repeated.

Nightmare flew into the two rings Amy created and dissolved with only his rank stars left. "Behold as darkness and light combine the true power of the Soul Edge is unleashed." Destiny chanted. "I Xyz-Synchro summon Soulborn Element-Nightmare Magi(ATK:7000-7500)." Nightmare reappeared with shining silver armor and the one and only Element of Magic in his breastplate. "I play Nightmare's Xyz ability, by discarding one overlay unit, he can convert a monster to our side. Welcome to team good-guys Ra." the element glowed and Ra stood by Destiny. "Next I play Ra's instant attack ability, by sacrificing 1000 life points, I can automatically destroy a monster." Ra exhaled and Uru exploded.

Andrew & Destiny:5000-4000

"This ends now Naraku. Nightmare, attack with Burning Phoenix Blade!" Nightmare swung the Soul Edge and a jet of flames hit the demon-kin.

Naraku & Shade:1000-0

"Game Over Naraku." Destiny said. "And since you'll be going to Tarturus, I'll hold on to Ra." Naraku smiled.

"Since you defeated me, I'll return the other signers to their former selves. You'll need all the help you can get for what's coming next. Beware, little girl. Beware the Seven Sins." both exploded and in their wake lay Bronze Dagger, Snails, Osiris, Starlight Glimmer, and Filthy Rich. Andrew debated with the rest what to do with them.

I know, the duel should have been longer, but I was kind of impatient to finish. Keep a lookout for The Brony Brothers: Sinful Lives.