Silva and Scáthach faced each other in the same spot where the fight with Gilgamesh took place, as the Demon King did not want to chance to destroy his underground complex by going all out against the Queen of the Land of Shadows. He could not afford to hold back, but before they started, Silva asked Scáthach with reluctance.
" Is there no other way?"
" All I ever wanted was a final defeat in which I gain release."
The Queen of Shadows stated curtly as she drew out her two red spears. The Demon King did not waste his breath and readied Snærkló as he prepared to kill the Servant before him. Clouds formed above them due to Silva's machinations, and as the rain fell on the two, they clashed at the first flash of lightning. The Demon King could not bring out his pseudo-Reality Marble as it takes too much time to set up, time that while Gilgamesh was arrogant enough to give him, Scáthach would not let a single opening escape her notice or spears.
The Servant deflected her opponent's attack to the side and used her free spear to pierce him but was met with Aura protecting him. Silva grabbed the red spear and pulled Scáthach closer, but she let go, then backed away and brought out another spear before launching six at him like missiles. The Demon King unleashed a massive blast of dark energy, which flooded the Lancer's vision, and she quickly cast some Runes to shield her. As the dark energy cleared in front of Scáthach, she found Silva missing, then promptly ducked to avoid being beheaded.
The Servant swept her spears as she crouched down at the Demon King, but he was as steadfast as a mountain as she felt the recoil of striking him. Silva then swung his polearm down, but Scáthach tumbled away. However, the Demon King caused lightning to rain down on the Lancer, which forced her to use Runes to shield herself as she was in no position to avoid the wide-scale force of nature. Scáthach blocked the bolt of lightning as Silva used Flash Step to close the distance and swipe at the Servant, but she deftly evaded his attack.
Silva then unleashed an Aura Slash at Scáthach in a wide arc, but she redirected the attack with skillful spear mastery and charged at the Demon King. They clashed at high speeds, two red spears meeting the exotic silver polearm. The sound of metal clashing against metal rang out and echoed at a furious pace. Silva was disarmed of his weapon by Scáthach, but he then drew out his claws as he cloaked himself with Dark Wrath. The Servant grinned as she saw that the Demon King was more skilled at using his claws over his polearm.
Scáthach's reach was met with Silva's flexibility as he batted and struck against the red spears. The few times the Demon King tried to grab the spears, he forced the Lancer to let them go and switch out for another spear stored in her shadow. Silva closed the distance by forcing the two spears in opposite directions, leaving Scáthach open, which he swiped with his claws, but the Servant was no stranger to unarm combat as she used a high kick aimed at her opponent's wrist.
Silva quickly grabbed Scáthach by the ankle and intended to slam her into the ground, but the Servant quickly planted her spears into the ground first to give her more leverage and use her free leg to kick away the Demon King. Lightning struck again at Silva's command and landed a blow on Scáthach. While the Servant was stunned for the moment, the Demon King tore at her with his claws but only barely drew blood, thanks to the bodysuit's defenses. Silva growled in annoyance at Scáthach's seemingly flimsy armor.
The Demon King fired another blast of dark energy at the Servant, but she leaped up into the air. The red spears lit up with power as Scáthach unleashed her Noble Phantasm.
" Gáe Bolg Alternative!"
Moving through the air with Runes being used as her platform, she almost instantly closed the distance and slashed with her red spears to cut through Silva's defenses, then used the final thrust to pierce his heart. The Demon King collapsed on top of the Servant as his dark cloak dissipated, and she said courtesy.
" You were an admirable warrior, Silva Branwen; This Scáthach will not forget you."
Silva then grabbed hold of Scáthach's arm as he concentrated Dark Wrath on the tip of his claws and tore through her from her hip to her shoulder. The Servant looked surprised as she croaked in confusion.
" How?"
With heaving pants, the Demon King explained how he still moved despite his heart being pierced by her spear.
" I... Wasn't... Sure... It... Would... Work... But... Your... Attack... Did... Not... Reach... My... Heart... Since... I... Opened... A... Portal... Within... My... Body..."
Silva pulled the red spear out from his chest as Scáthach lost the strength to grip her weapon. The Demon King gently sets down the Lancer on the ground as the clouds roll back to reveal the starry night sky. Scáthach then weakly said with a thin smile at learning how her Noble Phantasm was countered.
" I see..."
Silva laid her head on his lap and asked.
" Are you satisfied?"
" Yes..."
The Servant looked up at the night sky as blood seeped from her wounds and said.
" I never thought I would die under a beautiful night sky like this."
Scáthach reached for the stars, and Silva kept her company as she started to fade into golden particles. The Lancer manifested a red spear one more time in her outstretched hand and said with a proud smile.
" I, Scáthach, bequeath to you this spear, Silva Branwen. Proudly proclaim that you are the one to defeat this Scáthach as you continue your life's journey."
Silva grabbed the spear and felt it... Connect to him in a way he was unfamiliar with and wished Scáthach.
" May you find peace and love in your next life, Scáthach."
" This Scáthach has no interest in peace, but love sounds..."
And she returned to the Throne of Heroes with the memories of her final defeat.