Along the way. Although Kiritsugu is resistant to talk. He eventually loosened up and asked his unknown benefactor of the situation with Illya and Irisviel.
After all, Kiritsugu is not innately cold and heartless. That facade is just his mask as the Magus Killer. Not to mention, his memories of those days rotting away till his death after the 4th Holy Grail War had changed his temperament quite significantly.
His current opinion of Ray is a great benefactor that helped him reunite his shattered family and he is immensely grateful as both a husband and a father even if the reason for his aid is unknown.
Previously, he heard Ray mention he had formed a contract with Illya and the only kind of contract between Magus that comes to mind is the binding contract of Geis.
If Ray and Illya already have a binding contract of Geis in place, he can rest assured regardless of his true purpose.
However, to truly resurrect both him and Irisviel is quite farfetched for a powerful Magus to achieve with Magecraft.
Unless… Ray is a wielder of True Magic. However, that is impossible.
At least, from his observation as a slightly accomplished Magus, Ray's technique to employ his Spatial Magecraft look quite sloppy and unrefined even compared to himself for the caliber of a Magician.
More of a spell caster that simply use a Magecraft than a Magus that refine a Magecraft
Twenty minutes later, Ray and Kiritsugu returned to Einzbern castle.
Immediately upon arrival, they both saw Irisviel standing by the door still dressed in the Dress of Heaven waiting in anticipation upon sensing the presence of her Master. Standing beside Irisviel is Illya, her face radiant and no longer gloomy like before.
"Papa!"
Illya's face bloomed with joy and relief when the familiar face of his father appeared.
Illya sprinted forward and raced into the embrace of the stunned Kiritsugu while Irisviel stood still with a radiant smile.
Both husband and wife engaged in a silent conversation with their eyes as if to express their longing. But didn't show it directly in front of Illya to not spoil her joy.
Kiritsugu kneels down on one leg and opens his arm wide as Illya leaps into his embrace before they hug tightly. Illya rubs her cheek on Kiritsugu's chest as if to express all the sorrow and hardship she had endured with his absence.
On the side, Ray didn't disturb the father and daughter pair and instead walked up to Irisviel who looked prepared for his presence.
"I already heard the details of the deal between my Illya and you." She spoke, the gentle smile filled with gratitude on her face never faded.
"The Heaven's Feel. There's no need to seek the Greater Grail under the Ryuudou Temple since I as the Terminal of the Holy Grail possess this incomplete form of this True Magic once mastered by my predecessor."
"However…" Irisviel came to a hesitant pause as she looked awkwardly at Ray.
"The Heaven's Feel that I possess can't exactly be taught as it is the innate ability of my body as a Justeaze Series Homunculus."
Ray didn't look disappointed by her explanation. He nodded and shook his head.
"You needn't to worry. I can copy it myself. All I ask is to stretch out your hand."
Although confused, Irisviel still did as she was told and offered her hand which Ray held before closing his eyes.
Inside his mind, Ego proceeds with the scan on Irisviel's body and soul from the point of contact before copying the Third Magic, Heaven's Feel and Wish attribute.
Once Heaven's Feel had been copied, a great torrent of knowledge flooded his mind and brain. Any normal person would have their brain fried from the sheer amount of knowledge but Ray didn't even flinch as he absorbed everything with clarity.
After comprehending everything. Rather than calling it 'Magic' like Magecraft that is made up of magical formula and repeatable with sufficient understanding, the True Magic is closer to an Authority like the power of a Herrscher.
The moment he grasped Heaven's Feel, he resurrected Irisviel to test his new power.
Irisviel felt her soul in the Caster Class Servant body was pulled away from its vessel and began to elevate her soul.
The essence of the Third Magic, Heaven's Feel, is to enhance the soul and elevate it to be capable of interacting with the physical world without the usage of a body or vessel and turning it into a perpetual motion machine capable of generating its own energy. The immortality is just a side benefit that came with the transformation.
The clearest example of the expression of Heaven's Feel is the Servants. They are basically the bootleg version of the true ascended soul the Third Magic can achieve.
An entity that is entirely mental form, a soul, which can interact with the physical world. No different than humans with flesh and blood except they are made of Magical Energy.
They need no food for upkeep and only Mana to maintain their form. With enough Mana, even fatal injuries and lost body parts can be regenerated.
In the eyes of Illya and Kiritsugu, Irisviel's body simply glows as a dense amount of Magical Energy shimmer around her before it vanishes into her.
However, to Irisviel who had some understanding of the Third Magic as the Terminal of the Holy Grail. She can feel changes to her own body.
Even though she is no different to a Servant, the vessel granted by the Holy Grail when she was summoned as a Caster had now become her own vessel independent from the Greater Grail binding.
No longer is she dependent on Mana supplied by her Master and instead her own Saint Graph becomes a perpetual motion machine capable of generating Mana for herself.
In other words, she is fully revived and no longer just a soul temporarily inhabiting a vessel borrowed from the Greater Grail.
But, instead of joy. She lifts her head to stare at Ray in puzzlement.
By right, Ray is already qualified as a new Magician commanding the Third True Magic. However, she couldn't sense the connection to Akasha each Magician should have.
Sensing her confusion, Ray let go of her hand and explained briefly.
"Indeed I already own the authority of Heaven's Feel. However, I have a peculiar circumstance that prevents me from earning the acknowledgement of the Akasha."
After all, Ray is an Outer God in disguise. To acknowledge him as a Magician and granting him the qualification to access Akasha is no different from the Counter Force opening the door to allow the wolf to enter the sheep's pen.
Not to mention, his method of acquisition is more like plunder than earning the Authority of Heaven's Feel. Not that he particularly minds.
Endless supply of Mana from the root? He has it too.
Information recorded from the past, present and future in the Akasha? Not interested. Even if he did, Ego can dig up anything he needs.
All he cares and needs is authority and ability.
Next, Ray moves to Kiritsugu and helps his revival while conveniently copying his inherited Magecraft, Time Alter.
The Time Alter the Servant Kiritsugu possesses is a notch higher in quality compared to the one he possesses when he is alive.
In the hand of Kiritsugu, this Time Alter Magecraft is merely a Magecraft that can accelerate the caster's own time by deploying a temporal bounded field on the caster's body due to many constraints but mainly its severe Mana consumption. However, Ray has no such constraints.
Time Alter is a bona-fide time controlling ability and in Ray's hand, he can display its true might by deploying a bounded field beyond just his body.
Just imagining the scene where he can stop time like Dio Brando made Ray secretly giddy in heart.
"I am forever in your debt." Kiritsugu said emotionally. But his face remained composed as he held Ray's hand.
"If you have any needs, I will do my best to help as long as it does not touch my bottom line."
"No need." Ray replied decisively with a quick shake of his head.
"Everything I have done is for my own benefit."
Then he turned to Illya and asked.
"What about your Servant? Do you wish to restore his sanity? The limit of Heaven's Feel is not just reviving souls."
Illya immediately nods her head excitedly at this suggestion.
After all, Berserker is someone she had bonded with and supported her emotionally when she was at her lowest.
She is always dissatisfied that she cannot talk with Berserker despite having developed an understanding that words become unnecessary to understand Berserker's thoughts.
Still, she wouldn't hesitate at this chance and agreed before quickly summoning Berserker to her side for Ray to take a look.
Like before, Ray placed his hand on Berserker's arm to form a point of physical contact before he started modifying his vessel and Saint Graph all while secretly copying his martial techniques knowledge and most importantly, Berserker's Noble Phantasm to be grafted on his own avatar's soul.
Once he was done, he did not linger and bid the Emiya family a farewell as he still had one more stop before he had to rush back to Sirin's side.
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