In truth, Illyasviel didn't particularly mind Minamoto no Raikou's near-pathological possessiveness. After all, you can't really expect a homunculus created by the Einzbern family—deprived of parental love—to have any proper sense of values. Besides, Illyasviel herself had quite a strong possessive streak; otherwise, the original story wouldn't have had her turn Shirou into a doll and stash him in the basement.
"Commencing battle phase! First, Kiritsugu Emiya attacks Rin Tohsaka!"
Kiritsugu Emiya possessed an effect that increased his Attack Power by 1000 when targeting specific classes, and Rin Tohsaka happened to meet those conditions.
Rin Tohsaka stood no chance against Kiritsugu Emiya. A bullet pierced her skull instantly.
Rin Tohsaka's Life Points: 3000 → 1600
"Truly worthy of the title 'Mage Killer'! Its attack power in this instant rivals that of a top-tier Heroic Spirit! Player Illya still has a total of 5500 attack points on the field. Can Rin Tohsaka safely navigate this trial?!"
"Next, [Minamoto no Raikou], crush [Emiya]!"
Minamoto no Raikou, with her formidable 3000 ATK, charged at Archer. Even with the power of the Jeweled Sword, he was no match for her.
Archer's twin swords clashed with the tachi in Raikou's hands.
"Now! I activate [Explosive Ruby Magecraft]! I target one Servant and boost their ATK by 500!"
Rin Tohsaka revealed her last face-down card.
Emiya's attack power: 2500 → 3000.
With equal attack power, both servants should have been sent to the Graveyard simultaneously, but Archer stubbornly remained standing.
"Ruby Magecraft's effect prevents Archer from being destroyed in battle! Moreover, whenever he successfully destroys a servant in battle, I draw a card!"
"What a troublesome ability," Illya remarked. Though her strongest servant had been sent to the Graveyard, she showed no signs of distress. The unenhanced Raikou couldn't unleash her full potential.
"But this actually works to my advantage!"
The final Trap Card leaped from Illya's hand onto the field.
"Trap Card: [ Endless Martial Prowess ]! This card can be activated directly from your hand if a Minamoto no Raikou-related Servant on your field is destroyed! Special Summon one Minamoto no Raikou-related Servant from your hand or Graveyard to your field, and Special Summon one Mount Ōe-related Servant from your Deck or Graveyard to your opponent's field!"
Minamoto no Raikou: Attack Power 3000.
Shuten Dōji: 8-Star Assassin, Attack Power 2800.
"Ugh, disgusting! The stench of cattle and milk is revolting!"
A small girl with crimson oni horns materialized on Rin Tohsaka's field, facing Minamoto no Raikou, who towered over her by more than thirty centimeters. She pinched her nose in disgust.
"What a loathsome Noble Phantasm! Why am I cursed to be bound to this milk cow?!"
"On the contrary, I'm rather grateful for this Noble Phantasm. After all—it grants me the pleasure of severing your head once more!"
The Minamoto no Raikou summoned by Illya's Trap Card was free from any sealing effects. In her current state, she was terrifyingly powerful!
"Servants summoned by this card's effect are immune to all other card effects until the end of the next turn, except for those of 'Endless Martial Prowess' and Servants summoned by it! Therefore, Minamoto no Raikou and Shuten Dōji are currently only affected by each other's effects! The battle continues!"
The ill-fated connection between Shuten Dōji and Minamoto no Raikou wouldn't last long. Raikou launched another attack, her 200-point Attack Power advantage creating a seemingly insurmountable gap within the Duel's rules. A surge of purple lightning crackled from Raikou's blade, hurtling toward Shuten Dōji with unstoppable force.
"Next time we hang out, I hope to see that little golden brat again," Shuten Dōji said, licking her lips and facing Raikou's onslaught with a malicious grin. "If he's in my Deck, that means he's mine now!"
"Die!" Raikou roared, decapitating Shuten Dōji.
"Raikou's effect activates! When she destroys an opponent's Servant in battle, I can add an Equip Spell Card from my Deck to my hand. I choose 'Dōjigiri Yasutsuna' and equip it to Raikou."
Minamoto no Raikou's Attack Power: 3000 → 3000.
Raikou grasped her favored blade, nodding in satisfaction. Though her displayed Attack Power remained unchanged, Dōjigiri's effect wouldn't activate until the next turn.
"Main Phase 2: I activate the effect of Dōjigiri Yasutsuna, which can only be used during my turn. I send one Mount Ōe servant from my deck to the graveyard and draw a card!"
This effect is based on the legend of Minamoto no Raikou receiving a lavish reward from the Emperor after slaying an Oni.
"I'll set this card face-down in my back row and end my turn."
Illya had also exhausted her hand.
"My turn. Draw!"
Rin Tohsaka replenished her hand to two cards. She stared at Minamoto no Raikou, who was now immune to other card effects and could only be defeated in battle.
However, Illya's Einzbern strategy had kept Raikou's full abilities hidden, making Rin hesitant. She couldn't believe such a top-tier servant would only have one effect: destroying servants to gain Equip Cards.
"First, I'll use Maintaining Elegance! After banishing the top ten cards of my deck face-down, I draw two cards."
Rin performed her standard card replenishment.
"Next, the Jeweled Sword effect! I search my deck for a Jewel Magic card and add it to my hand! I'll take Ruby Magecraft!"
Rin's strategy was clear: she intended to use the same tactic to send Raikou to the graveyard again.
"I Normal Summon Tokiomi Tohsaka and add Sapphire Magecraft to my hand!"
"Kiritsugu Emiya, I never expected to run into you in a place like this."
Tokiomi Tohsaka spotted his old rival. Though he didn't voice his disapproval directly, he still couldn't quite approve of Kiritsugu's methods.
Kiritsugu nodded in acknowledgment. The two middle-aged men had little in common and nothing to discuss.
"Entering the battle phase! I activate [ Ruby Magecraft ] on [ Emiya ] again!"
[ Emiya ]'s Attack Power: 2500 → 3000.
Rin Tohsaka's Life Points: 1600 → 1850.
Illya's Life Points: 3000 → 2750.
"It's an honor to face the legendary Minamoto no Raikou once more."
Archer drew his Jeweled Sword and engaged Raikou in another blade-to-blade duel, but this time neither gained the upper hand.
"Did you know that after Raikou slew Shuten Dōji, she contracted malaria and was bedridden?" Illya began recounting the legend. "Even in that weakened state, she used Hizamaru to slay the earth spider who, disguised as a demonic monk, had come to assassinate her. Therefore, when [ Minamoto no Raikou ] is destroyed by battle, you can banish a non-humanoid Servant from your Graveyard as a substitute!"
Protected from other card effects and immune to destruction, Minamoto no Raikou was now an impenetrable fortress.