3rd POV:
Dextra took out a coin from her pocket and throw it high on the sky.
Nistro: "Head!"
Ryuji: "Tail!"
Dextra catch the coin and open her hands, then she shows the coin to others "Tail"
Ryuji smirk a little "look like my luck today isn't bad. Draw!"
"I normal summon Rescue Cat, then activate it effects, I can send this card to the GY; Special Summon 2 Level 3 or lower Beast monsters from my Deck, but their effects are negated, also they are destroyed during the End Phase."
"I special summon two Peropero Cerperus from my deck."
[Peropero Cerperus, atk: 0]
The white cat that just appear on Ryuji field directly jump to his graveyard and from his deck, two three heads dog with overwhelming big eyes jump on his field.
'A new monster?' Dextra and Nistro thought at the same time, they have never seen Ryuji use that monster before.
Ryuji notice their confused look and chuck. "Did you guys really think I go all out when fight with other students? Then let me show you what my true deck really is."
"I overlay both Cerperus to xyz summon Leviair the Sea Dragon in defense position."
[Leviair the Sea Dragon, def: 1600]
"Then I activate Last Will, if a monster on my side of the field was sent to your Graveyard this turn, I can Special Summon 1 monster with an ATK of 1500 points or less from my Deck once during this turn. You know what I will summon right?" Ryuji slowly take out a card from his deck and put it on his duel disk. "I special summon Rescue Rabbit!"
[Rescue Rabbit, atk: 300]
Dextra and Nistro instantly tense up, they know far to well what terror this innocent looking rabbit was gonna bought to them.
" I activate Rescue Rabbit effect; I can banish this card; Special Summon 2 Level 4 or lower Normal Monsters with the same name from my Deck but destroy them during the End Phase. I special summon two Sabersaurus from my deck."
[Sabersaurus, atk: 1900] x 2
"I overlay both of them to xyz summon Evolzar Dolkka!"
[Evolzar Dolkka, atk: 2300]
"Then I activate Foolish Burial, I can send 1 monster from my Deck to the GY. I send Stegocyber to the graveyard and set two cards. Then I activate Leviair effects, detach 1 material from this card, then target on level 4 or lower monster; Special summon that target to the field. Return Rescue Rabbit!"
[Rescue Rabbit, def: 100]
"I end my turn."
Just the first turn but Dextra and Nistro already feel an overwhelming pressure on their body, Evolzar Dolkka can negate monster effects two-time, Rescue Rabbit is back on the field that mean another Evolzar or other rank 4 monster since they don't know what card he takes from Mr.Heartland. And he can still summon Rescue Rabbit back one more time in his turn since Leviair still have 1 material.
But the thing they most worry about is actually his graveyard, Cerperus and Stegocyber. Even though they don't know what those cards can do but without a doubt those cards have effects activate from graveyard.
If not, then he can just summon two level 3 normal monster to summon Leviair since Rescue Cat will negate that monster effects anyway but if it an effect that can only activate when send or if it was in graveyard then that make sense.
Dextra and Nistro look at each other for a moment to decided who take the next turn. Dextra shake her head implies that she can't deal with Ryuji field.
Nistro took a deep breath and draw a card out of his deck. "My turn, draw!"
"I activate Trap Bootster by discard 1 card in my hand. This turn, I can activate 1 Trap Card from your hand. I activate Ultimate Offering from my hand."
"During my Main Phase or my opponent's Battle Phase: I can pay 500 LP; immediately after this effect resolves, Normal Summon/Set 1 monster. I pay 500 LP to normal summon 2 times."
[Dextra/Nistro, LP:8000 -> 7500]
"I summon from my hand Heroic Challenger - Night Watchman, Heroic Challenger - Extra Sword both in attack position."
[Heroic Challenger - Night Watchman, atk : 1200]
[Heroic Challenger - Extra Sword, atk: 1000]
"Battle Phase! I use Night Watchman to attack Leviair, then activate its effect. If this card attacks a Defense Position monster your opponent controls, before damage calculation: I can destroy that monster."
Night Watchman raise its sword and launch at Leviair. 'Now he will activate Dolkka effect, that one material less.' In a 2v1 like this Ryuji have a huge disadvantage in resources from the start so he wants to waste some of Ryuji remaining resources to create an opportunity for Dextra to finish him off.
But contrast to Nistro thought, Ryuji didn't activate Dolkka effect. "I activate Negate Attack! When an opponent's monster declares an attack: Target the attacking monster; negate the attack, then end the Battle Phase. Your Battle Phase end now!"
"Tch! Then I overlay both monster to xyz summon Fairy King Albverdich in attack position! Extra Sword effect, an Xyz Monster that was Summoned using this card as Xyz Material gains 1000 atk." Nistro use both his heroic to summon the reward he gains from the practice exam.
[Fairy King Albverdich, atk: 2300 -> 3300]
Nistro summon this monster purely to be a wall again Ryuji monster, although Albverdich can detach 1 material to make all non-Earth monster lose 500 atk but with full material Dolkka on the field, he never dares to. He can also choose to summon Excalibur but that card basically useless for now.
"I activate Xyz Treasure, it allows me to draw 1 card for each face-up Xyz Monster on the field. On the field currently have Leviair, Dolkka and Albverdich so I get to draw 3 cards. "Nistro quickly draw three cards from his deck then set 1 card. "I set 1 card and end my turn."
Ryuji quickly draw 1 card from his deck: "Then it's my turn once again, draw! I activate Graceful Charity, it let me draw 3 cards, then discard 2 cards."
"I activate Rescue Rabbit effect-" Ryuji got cut off by Nistro.
"I activate my set card Breakthrough Skill; I can target 1 Effect Monster my opponent controls; negate the effects of that face-up monster my opponent controls until the end of this turn. No more dino!" Nistro shout out loud when he activates his trap card, that rabbit give him some serious PTSD.
"Trying to stop me from xyz? Then you underestimate me too much! I activate effect of Carboneddon that I just send to the graveyard. You can banish this card from your GY; Special Summon, from your hand or Deck, 1 Level 7 or lower Dragon Normal Monster in face-up Defense Position. Come here, Luster Dragon #2!"
[Luster Dragon #2, atk: 2400]
The only purpose of these two cards is for his rank 6 monster, Luster Dragon #2 have the highest atk among normal level 6 dragon, in the future if he adds synchro to extra deck, he will replace it with Labradorite Dragon.
"Next I tribute Rescue Rabbit to summon Frostosaurus in attack position."
[Frostosaurus, atk: 2600]
'2 level 6 monster, so here it comes Ryuji new monster.' Dextra and Nistro now fully focused to see which monster Ryuji deem worthy to be in his deck.
"I overlay both Frostosaurus and Luster Dragon #2 to xyz summon, rank 6 Dragonlark Pairen!"
The two monsters turn into two rays of light and flew up and form a portal in the sky. From within the portal, a creature, half dragon half bird flew out.
[Dragonlark Pairen, atk: 2700]
"I activate Spider Web (anime), it allows me to select 1 card in my opponent graveyard that was sent there the previous turn and add it to my hand." A phantom of a spider appears behind Ryuji, it shoots string into Nistro duel disk and pull out one card. "I target Xyz treasure in your graveyard."
He shows the card to other two, "You two know what this card do right?" He smiles a little under other two darken face. "I activate Xyz Treasure, right now there is 4 xyz monsters on the field so I draw 4 cards." He quickly draws 4 cards out of his deck with a happy smile 'this card use even better than Pot of Greed.'
"Finally, I activate my set card, Book of Moon to change Albverdich to face-down defense position. Enter Battle Phase! I use Dolkka to attack Albverdich." Evolzar Dolkka charge fire energy into it mouths then shoot a fireball at Nistro monster destroy it.
Dextra instantly worry, now they're have nothing to stop Ryuji attack. Nistro see her worry and said with calm tone "don't worry, everything is still within my calculated."
Ryuji can't help but mock him a little. "Wow, just morning you still can't remember multiplication table but now you can calculate this far ahead, good job!" Although Ryuji is praise him, but Nistro know full well not a single word of it is mean to praise.
"Don't look down on me!"
"Tch! What do you mean look down? When we talk have you ever see I look down on you? I away look up." Nistro turn his head away not utter another word.
"Haha, then let's see what's your plan. Pairen direct attack!"
"Hmph! Don't forget my trap card, I activate Ultimate Offering once again, I normal summon from my hand Obnoxious Celtic Guard in defense position. This card cannot be destroyed by battle with a monster that has 1900 or more ATK."
[Dextra/Nistro, LP:7500 -> 7000]
[Obnoxious Celtic Guard, def: 1200]
"Heh~ who would have thought you will use this card. Alright, I activate Leviair effect to bring back Carboneddon in defense position and set 2 cards, I end my turn."
[Carboneddon, def: 600]
Nistro: I do everything I could, now do your best!
Dextra exhale then draw a card. "My turn, draw!"
"First, I activate Mystical Space Typhoon to destroy your right set card." As the raging typhoon form in the field and destroy Ryuji set card, both of them was able to see it "Solemn Judgment", they both breaths out 'we dodge a bullet here'. "Next, I activate Reinforcement of the Army to add 1 Level 4 or lower Warrior monster from my Deck to my hand. I add Blue Mountain Butterspy to my hand."
"Then I normal summon Morpho Butterspy and activate Blue Mountain Butterspy effect in my hand, when I Normal Summon a Warrior monster: I can Special Summon this card from your hand."
[Morpho Butterspy, atk: 1200]
[Blue Mountain Butterspy, atk: 0]
"I overlay both monster to xyz summon Blade Armor Ninja in attack position!" Dextra reward in practice exam, perfect for her warrior deck.
[Blade Armor Ninja, atk: 2200]
"Here I come Ryuji! I activate Berserk Scales, target 1 face-up monster I control (except a monster that is attacking directly); it gains 1000 ATK, also it cannot attack directly for the rest of this turn. I attack your Evolzar Dolkka!"
[Blade Armor Ninja, atk: 2200 -> 3200]
The monster draws one of its katana and swings it at Evolzar Dolkka slice it in half.
[Ryuji, LP: 8000 -> 7100]
Dextra and Nistro look at each other with excitement in their eyes, after a lot of hardship they finally make Ryuji lose LP.
Dextra excited continue her attack "And because Dolkka have leave the field, you can't negate my monster effect anymore! I activate Blade Armor Ninja effect; I can detach 1 Xyz Material from this card to target 1 "Ninja" monster I control; it can make a second attack during each Battle Phase this turn. I target Blade Armor Ninja itself and attack your Dragonlark Pairen!"
Just as Blade Armor Ninja draw it second katana and launch at Pairen, a black mist come out of Ryuji graveyard and wrap tightly around the ninja destroy it completely. The mist then turns into a phantom of a dog with three heads.
Dextra and Nistro stare in shock as Ryuji take a card out of his graveyard. "Peropero Cerperus effect, if I take damage by battle or an opponent's card effect while this card is in the GY: I can banish this card from the GY, then target 1 card on the field; destroy it."
"So... what are you gonna do now?"
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Now I feel the pain of making OP MC, it's too hard to make a duel without making it boring.