Rumble…!
The ground trembled, and the force of the impact shook the trees. It was the shockwave from a colossal power. And that shockwave was…
"I'm going to die at this rate!!!"
"It's alright, I'm here for you."
"■■■■■!!!"
…the pursuit of a gigantic demonic beast. And fleeing from it were the two of us, Medb and myself. In truth, there was no need to run, but this was to build up Medb's basic stamina. The plan was that if things seemed too much for her, I would simply dispose of the beast.
It was a ridiculously simple-minded method, but what can you do? This is the Celtic way.
"I… I can't— anymore—!"
Medb, who had been running, finally reached her limit, pitching forward and collapsing onto the ground. I suppose this is enough for today.
Screech…!
I dug my heels into the ground to halt my momentum, then pivoted sharply and threw a straight punch.
CRACK!!!
The force of the punch, amplified by inertia, was more than enough to kill the demonic beast in a single blow. Its skull shattered, and it fell to the ground.
"Huff… huff… you're completely… mad, aren't you! Cough, cough!"
"This is how one grows up. The weak would have all died long ago. Isn't that why the Celts are so strong?"
"Well, that's true, but…"
"In the first place, this land of Ulster is effectively the last remnant of the Age of Gods. Being near Britannia, the Navel of the Planet, there is no other place where one must be stronger to survive. That is why you must become strong, do you understand?"
"But this is just too barbaric…!"
In all other regions, the Age of Gods ended long ago. In the current 1st century BC, the last vestiges of that era remain only in Ireland and Britain. Or perhaps in that Mary Sue of a nation, Japan? That place has always been ancient.
"There is a saying: 'If your head is no good, your body must suffer.'"
"What's that? It sounds like a sound argument."
"But in the Celtic lands, the rule is that if your body is strong, your head doesn't have to suffer."
"...Hey, could you stop speaking in sound arguments?"
"Isn't that the way of the Vikings? Well, not that we are Vikings."
"What are you talking about... Fergus, do you have a geas or something?"
"No. I don't bother with such things."
"You don't? Are you even a warrior?"
"Honestly, things like a geas are just a nuisance. I would rather make a different kind of vow. It's better than being called a coward and then regretting a choice at a critical moment in life because of some damn geas."
"It's infuriating how you only speak in sound arguments."
"So you shouldn't bother with useless things like a geas either. And since you've rested enough, let's do some strength training."
"Waaaaah!"
I will raise my child to be strong...! Well, she isn't my child, but still.
On another note... I wonder if Setanta is growing up well?
Cú Chulainn has already been born. I am in my late teens, and Conchobar is around the same age. He is still young, but in a few years, he will become a young warrior. At the age of seven, one can be said to begin the path of a warrior. Cú Chulainn is five now... so there are about two years left. I plan to stay here for a little over a year before going back. It is thanks to my careful actions that the old king is still alive. Otherwise, he would have already passed, and I would have inherited the throne. I told him to take good care of his health, so he should be fine for a while, but his age is still a concern...
Conchobar will be fine, but I'm worried about Cú Chulainn. Although I am technically his stepfather, everyone knows that his true father is the king of the gods. And his mother is alive and well. But I have too much on my plate to worry about my nephew. I need to become stronger, I need to become smarter, and I need to rehabilitate this villainess.
This is a tough life...
On top of that, my knowledge of Celtic mythology isn't perfect, so I'm doing all this based solely on my knowledge from Fate. I don't know what will happen in the future. The big thing I know is Cú Chulainn killing his own son? It might even be a daughter; Type-Moon style gender-bending is common, isn't it? And was it Calatín's sons? I remember something like that. My knowledge is limited, so I'm at a loss...
"...This is all for your own good, Medb."
"What do you mean, for my good... isn't this all for your own future?"
"If you grow up to be a villainess, you will die by being struck by a flying piece of cheese."
"...Really?"
"If you don't want to be recorded in history as having died such a pathetic death, you'd better train hard."
"Eh... you're lying, right? How can a person die from being hit by cheese?!"
"There are heroes who have died while taking a dump. And I do not lie. So, you had best behave."
"...No, seriously?"
"Yep."
"...I shouldn't be motivated by something like this..."
"Haha."
For now, let's focus on Medb. In the Ulster Cycle, the biggest problems are Medb and Conchobar. I have to rehabilitate Medb first before I can move on to the next step.
"Come on, no slacking! Let's exercise! We have to avoid that future where you get killed by cheese!"
"Damn it... how did I end up..."
Can I successfully raise Medb in the Land of Shadows for several months while deliberately avoiding Scáthach? It's only the second day... but it looks like it's going to be a rough road.
Still, I can do this...!
...Or so I thought.
"F-Fergus..."
"I didn't expect to encounter a beast of this caliber so soon."
About a month later, as we were camped by the sea, it happened.
A colossal monster appeared with the waves. I had seen it before. Its form was depicted on a Craft Essence in FGO, and it was one of the most powerful creatures in the Land of Shadows. The very demonic beast whose remains became the raw material for Gáe Bolg.
The Beast of the Waves, Curruid.
Despite an appearance reminiscent of a coral reef, its hide looked like a suit of armor. I wondered if I could even win if I went all out.
"W-what do we do, Fergus! Let's run!"
"An Ulster warrior, turn his back and flee? Well, I suppose I could... but now is not the time, Medb. Wait here. The barrier will protect you. You trust me, right?"
"No."
"Please try... Anyway, just wait. Tonight's dinner has been decided."
Shing…
For the first time since coming to the Land of Shadows, I drew my sword for battle. It was Caladbolg, which I had been carrying in the form of a small, easy-to-carry dagger. In response to my will, the blade elongated into a slender form, just like Emiya's projected Spiral Sword. This form was much more convenient for combat. I had no intention of fighting with a sword that was more like a blunt weapon, as the original Fergus did. That form was only necessary for its True Name release.
"Well now, shall we have a go, monster of the Land of Shadows?"
"──■■■■!!!!"
RUMBLE RUMBLE RUMBLE!!!
The beast's roar alone made the coastline tremble. Inside the barrier, Medb was terrified and slumped to the ground.
"Then, let us begin."
Creeak... Creeeeeeaaaaak──!
"Revolve. And reveal your light. Before me stands the Beast of the Waves, a denizen of this spectral land! I shall show you but a fragment of the Spiral of Rainbow!"
The light of the rainbow began to rotate slowly. Its power was, for all intents and purposes, that of the strongest demonic sword. No, it was not even a demonic sword. It was the prototype of all holy and demonic swords, a Noble Phantasm said to have been forged from the remains of a god who died during Sefar's invasion. If its true power were to be fully unleashed, it could pulverize not just an island, but even part of a continent with its massive spiral of light.
The original Fergus had expended his Spirit Origin in America to wipe the whole country off the map, and in Agartha, he had actually obliterated an entire island. Even a clumsy sword-beam unleashed in anger could level three hills.
The spiraling sword, which had been rotating slowly, began to spin violently. It illuminated the coastline with the brilliant light of a rainbow. I gripped Caladbolg with both hands, raised it high into the air, and then swung it down with all my might.
"{Caladbolg}(Rainbow Sword)!!!!"
KRAKOOOOOOOOOOM!!!!
A massive spiral of light shot forward, rotating as it flew. A beam of blue light shot out from Curruid's mouth. The two forces clashed, but the moment I poured more power into Caladbolg, the rainbow-colored flash spun with even greater force, swallowing Curruid whole.
The earth shook, but Caladbolg, used as a sword to strike an enemy rather than to destroy the terrain... had recreated the miracle of the Red Sea.
"The sea... has parted."
"Hmm... even though that wasn't my full power, this is the result. Truly worthy of being the prototype of all holy and demonic swords. They call it an Anti-Army Noble Phantasm, but isn't this a true Anti-Fortress or even Anti-Country Noble Phantasm?"
To call this Anti-Army is a gross understatement. How is this Anti-Army? Emiya, you couldn't even reproduce a fraction of the real Caladbolg's power. If it were the real thing, you could have wiped Fuyuki City off the map.
Curruid was dead. However, while its outer scales were completely shattered, its corpse seemed to be intact. As long as the bones were intact, Gáe Bolg could probably be made. Well... I'll have to offer it to Scáthach, though.
"Well then, shall we butcher it and have dinner, Medb?"
"...Fergus, you really are strong."
"In this case, it's the power of the Noble Phantasm. The Noble Phantasm is strong, not me... This is not what I am aiming for. I seek a strength that is my own."
Scáthach can use her god-slaying spear techniques, including her spatial-piercing strikes, even without Gáe Bolg. The moment one becomes dependent on a Noble Phantasm, they become useless. Look at Kojirou, who possessed incredible skill in swordsmanship and close combat despite not having a Noble Phantasm. And Hector was a match for Achilles, who was loaded with Noble Phantasms. Unless you have as many Noble Phantasms as Gilgamesh, you shouldn't rely on them. Honestly, what could Saber do without Excalibur? She would probably even lose to Medusa.
Or maybe not.
The point is... I can't just rely on Caladbolg; I need to become stronger myself.
"One must not rely solely on their weapon. I'm not saying you shouldn't use weapons, but you shouldn't be dependent on just one. You must prioritize your own skill, so that you can pick up any of the countless weapons that have fallen on the battlefield and fight without issue. The moment you become dependent on your Noble Phantasm, you become a worthless piece of trash who can't do anything without it."
What could Gilles de Rais do without his spellbook? It's the same thing.
"...Just now, that was incredible."
"I'm glad you realize it."
"Wow... look how shameless you are."
"Haha."
Still, it seems that our life in the Land of Shadows is proceeding smoothly.