Kaito vs Ren

Turn 1 (Kaito)
LP: Kaito 4000 -- Ren 4000
 * Kaito sets a monster.
 * Kaito activates Allure of Darkness, drawing 2 cards and removing Red-Eyes Black Dragon from play.
 * Kaito sets 1 Magic or Trap Card.

Turn 2 (Ren)
LP: Kaito 4000 -- Ren 4000
 * Ren summons Bow of Swallowtail Crest in Attack Position ( 400 Atk /1400 Def).
 * Ren Special Summons Arrow of Swallowtail Crest with its effect and releases it with Bow of Swallowtail Crest's effect to increase Bow of Swallowtail Crest's Atk by 1000. Bow of Swallowtail Crest ( 400 ↑ 1400 Atk /1400 Def)
 * Ren adds another Arrow of Swallowtail Crest from his deck to his hand.
 * Bow of Swallowtail Crest attacks Kaito directly through its effect. (Kaito 4000 ↓ 2600)
 * Ren sets 2 Magic or Trap Cards.
 * Bow of Swallowtail Crest's effect expires at the End Phase. Bow of Swallowtail Crest ( 1400 ↓ 400 Atk /1400 Def)

Turn 3 (Kaito)
LP: Kaito 2600 -- Ren 4000
 * Kaito summons Dark Dragon Hatchling in Attack Position ( 800 Atk /500 Def).
 * Kaito activates Dark Dragon Hatchling's effect, releasing it to Special Summon Red-Eyes Black Dragon ( 2400 Atk /2000 Def) from his hand.
 * Kaito activates Inferno Fire Blast to inflict 2400 points of damage to Ren.
 * Ren activates Hanewata's effect, discarding it to reduce the effect damage to 0.

Turn 4 (Ren)
LP: Kaito 2600 -- Ren 4000
 * Ren summons Bee Square in Attack Position ( 500 Atk /400 Def).
 * Ren Special Summons Arrow of Swallowtail Crest with its effect and releases it and Bee Square to draw 2 cards.
 * Ren adds another Arrow of Swallowtail Crest from his deck to his hand.
 * Ren activates Last Will, Special Summoning Rapier of Swallowtail Crest in Attack Position ( 1400 Atk /600 Def).
 * Bow of Swallowtail Crest attacks Red-Eyes Black Dragon.
 * Ren activates Feint Strike, switching the battling monster to Rapier of Swallowtail Crest and halving Red-Eyes Black Dragon's Atk and Def. Red-Eyes Black Dragon ( 2400 ↓ 1200 Atk /2000 ↓ 1000 Def)
 * Red-Eyes Black Dragon is destroyed. (Kaito 2600 ↓ 2400)
 * Ren activates Sword of Warrior's Soul, equipping it to Rapier of Swallowtail Crest, removing the destroyed Red-Eyes Black Dragon from the game and increasing Rapier of Swallowtail Crest's Atk by half of Red-Eyes Black Dragon's. Rapier of Swallowtail Crest ( 1400 ↑ 2600 Atk /600 Def)
 * Rapier of Swallowtail Crest attacks Kaito's Set monster.
 * Dandylion is destroyed, Special Summoning 2 "Fluffy Tokens" (0 Atk/ 0 Def each) with its effect.
 * Ren sets 1 Magic or Trap Card.

Turn 5 (Kaito)
LP: Kaito 2400 -- Ren 4000
 * Kaito activates Heaven's Lost Property, drawing 3 cards and discarding Red-Eyes Black Dragon and Meteor Dragon.
 * Ren discards Arrow of Swallowtail Crest and Swallowtail Oath.
 * Kaito activates Dragon's Mirror, removing Red-Eyes Black Dragon and Meteor Dragon to Fusion Summon Meteor Black Dragon ( 3500 Atk /2000 Def).
 * Meteor Black Dragon attacks Rapier of Swallowtail Crest.
 * Ren releases Bow of Swallowtail Crest with Rapier of Swallowtail Crest's effect to negate the attack and increase Rapier of Swallowtail Crest's Atk by half of the attacking monster's Atk. Rapier of Swallowtail Crest ( 2600 ↑ 4350 Atk /600 Def)
 * Kaito sets 2 Magic or Trap Cards.

Turn 6 (Ren)
LP: Kaito 2400 -- Ren 4000
 * Ren summons Axe of Swallowtail Crest in Attack Position ( 1800 Atk /1200 Def).
 * Rapier of Swallowtail Crest attacks Meteor Black Dragon.
 * Kaito activates Proof of Powerlessness to destroy all of Ren's monsters of Level 5 or lower.
 * Ren activates Swallowtail Phalanx, releasing Axe of Swallowtail Crest to negate the destruction and draw 1 card.
 * Meteor Black Dragon is destroyed. (Kaito 2400 ↓ 1550)
 * Ren sets 2 Magic or Trap Cards.
 * Rapier of Swallowtail Crest's effect expires at the End Phase. Rapier of Swallowtail Crest ( 4350 ↓ 2600 Atk /600 Def)

Turn 7 (Kaito)
LP: Kaito 1550 -- Ren 4000
 * Kaito activates Return from the Different Dimension, paying half his life points (Kaito 1550 ↓ 775) to Special Summon his 3 removed-from-play Red-Eyes Black Dragons ( 2400 Atk /2000 Def each).
 * Kaito activates Hurricane to return all Magic and Trap Cards on the field to their owners' hands.
 * Since Sword of Warrior's Soul is no longer on the field, Rapier of Swallowtail Crest's Atk returns to its original value. Rapier of Swallowtail Crest ( 2600 ↓ 1400 Atk /600 Def)
 * Red-Eyes Black Dragon destroys Rapier of Swallowtail Crest. (Ren 4000 ↓ 3000)
 * The 2 other Red-Eyes Black Dragons attack Ren directly. (Ren 3000 ↓ 0)

Kaito wins the Duel.