Knight of Treachery
Next Shiro battles another Kamen Rider known as Incisor, then a servant name Lancer/Cuchulaina and unknowingly summons his own servant which is the Knight of Treachery.
Disclaimers: I own nothing
Emiya Household Storage House
"I now proclaim. . .thou shalt come before me! My fate is with thy sword! Obey the summons of the Holy Grail! If thou obeyest my will and reason answered! I hereby pledge. . .I shall be all that is good throughout eternity! I shall suppress all evil throughout eternity! Thou the seventh heaven, clad in the great trinity of language. . .emerge from the circle of constraint, thou guardian of the scales!"
What Shiro is doing in his Kamen Rider Dragon Knight is performing an identical traditions that Knights do in the past. (Notes: I have no clue what the word of the tradition is but I'm talking about is Knights are on their knees and holding their swords with both hands but the point of blade is on the floor) Shiro is on his knees and holding his Broadsword with both hands and saying random words like the traditions that Knights do in the past.
"I'm pretty good on that made up Knight tradition", Shiro demorphs and leaves the storage room but unknown to him a strange circle appears on the floor where he was originally standing on and the circle starts to glow.
XXX
"Shiro honey can you come with me to the store I need buy some stuff", Irisviel asked Shiro to accompany her to the store.
"Sure mom", Shiro can do that.
"Oh one more thing, no bikes."
"Okay we walk then", it's not like his mom hates bikes it's just that she likes exercising her feet.
XXX
On the streets
"Hey Shiro did you hear that?" Irisviel can hear the noise that's coming from Ventara.
"You can hear it too mom?" He asked her if she really hears it like him.
"Loud and clear Shiro", the only explanations why she can hear it is because she is a homunculess.
"We have a visitor coming from Ventara."
"What's Ventara?"
"No time to explain right now mom, find me a mirror or reflective surface", Shiro said then both he and Irisviel went looking for a mirror or reflective surface.
"You might want to step back mom", Shiro said to her after finding a window.
"What are going to do Shiro", she asked him as he pulls out his Advent Deck.
"Just watch Ms. Einzbern", Ayaka who just showed up told Irisviel to watch what happens as Shiro slips his Advent Deck into the belt buckle.
"Kamen Rider! Shiro morphs into Dragon Knight much to Irisviel's surprise and proceeds to Ventara.
"Kamen Rider?" Irisviel wonders what that means.
"Kamen Riders are superheroes of Ventara, Len told me and Shiro that", Ayaka tells Irisviel.
"Who's Len?"
"He's another Kamen Rider known as Wing Knight", Ayaka tells her who Len is.
XXX
Ventara
Shiro arrives at Ventara and looks around for any sign of a Mirror Monsters. Shiro looks to the left and found them, it's the same Gelnevts again and a humanoid grab next to them, that humanoid grab is Volcancer and he's a Mirror Beast use by a Kamen Rider which is unknown to Shiro.
"There you all are!" Shiro grabs his Advent Card and slips it into his Dragon Gauntlet.
SWORD VENT
Shiro grabs his Broadsword then attacks all of them at once, he slashes and defeats several Gelnevts the proceeds on Volcancer but it grabs his right arm with it's pincer on the left then tosses him into a wall. Shiro gets back on his feet but before he can attack Volcancer again the same vehicle he use to enter Ventara appears and the driver emerge from it.
"Your a Kamen Rider!" Shiro said after recognizing the symbol on the belt buckle.
"Perfect timing", but the perfect timing is only for Shiro to get attacked by the new Kamen Rider.
"Hey wait a minute! I'm not the enemy here!" But the new Kamen Rider is not listening and continues to batter him.
"I'm Shiro Emiya, what's yours", Shiro introduce himself while blocking the new Kamen Rider's Pincer Gauntlet.
"Shut up and fight Shiro", that's the reply Shiro gets from the new Kamen Rider known as Incisor.
"Oh not you again", Shiro said after being strucked in the back by Volcancer.
"What is going on here?" Shiro asked himself because he's seeing is Incisor and Volcancer working together.
"If you want answers Dragon Knight Shiro, Volcancer is my contract", Incisor spill out an answer to him.
"You pick one hell of time to tell me that", Shiro said while Incisor draws a Advent Card then slips it into his Pincer Gauntlet.
STRIKE VENT
Incisor right arm is fitted a bigger Pincer Claw, back in Fuyuki Len arrives to aid Shiro but instead he does nothing to help him but watches the battle. On Ventara, Shiro finds himself outmatched by Incisor and Volcancer, so he's force to retreat back Fuyuki.
XXX
"Man I thought all Kamen Riders are supposed to be good", Shiro said to himself after exiting a reflective surface and demorphs.
"Some way of me saying easy money", Kamen Rider Incisor demorphs and reveal himself to be Shinji Mato said after exiting Ventara.
XXX
Emiya Household
"WAH!" Shiro just came home only to find Len there with his mom, Ayaka, Sakura, and Ms. Taiga having supper with them.
"Hey Shiro I asked that if can join them for supper and your mom agreed to let me join", Len answer while Shiro had his right eyebrow twitching.
"Sit down and have dinner with us Senpai", Sakura tells him to sit down and join them which Shiro did.
XXX
Elsewhere
"Mr. Connors I will continue my job as long I get what you promise me", Shinji talking to man name Walter Connors in reality was the Kamen Riders archenemy Xaviax disguise as a man.
"Oh don't worry Shinji you'll have what I promise you, once you vented both Wing Knight and Dragon Knight", as Shinji leaves Xaviax looks on the reflective surface of a car's window, he's disguise as man but on the reflection he's still the real him in the Karsh Armor.
XXX
Emiya Household
"Well will see you tomorrow Shiro and Ms Einzbern", Ms. Taiga waving goodbye to Shiro and his mother.
"Bye Senpai", Sakura said goodbye.
"See ya Shiro", Ayaka said her goodbye to Shiro.
"Well everybody else is gone it's time for me to leave as well."
"You know I can't believe you just told everyone about the Kamen Riders, the mirror monsters, Ventara and Xaviax", earlier right after Shiro joins them for supper Len told all of them everything he knows but at first not everyone believes him but was then convinces when Len morphed.
"Your mom, your friend Ayaka, Ms. Taiga and Sakura have already seen it, so there's no point on keeping them in the dark."
"Oh you win", Shiro said and put his palm on his head and Len leaves.
XXX
Tennis Field nearby
"Archer I presume?" The man in blue tights wielding a Lance Staff said.
"That's right Lancer", Archer relied and summons 2 Swords then they charge.
"Archer, defeat Lancer!" Rin orders her servant Archer to attack and defeat Lancer.
XXX
Emiya Household
The clash of Archer's and Lancer's weapons was loud enough for Shiro to hear, he quickly gets out of bed, get's dress. grabs his Advent Deck and leaves the house without alerting his mother to check what's going on.
"It had to be another mirror monster running about in this area", Shiro doesn't know it's not a mirror monster's doing since he was told about them not anything else.
XXX
Back on the tennis field Lancer and Archer continue their battle with none gaining the upper hand, most of Archer's weapons broke caused by Lancer but he was still able summon more Sword-Like weapons.
"We have a visitor", Lancer said turning to the right spotting Shiro behind the fence of the tennis field.
"He's mine to kill", Lancer shifts his battle away from Archer and goes after Shiro.
Shiro runs for his life as Lancer tries to kill him, Shiro runs back to his home while dodging several strikes from Lancer's Staff. Eventually the chase comes to a stop when Shiro gets cornered in the storage room.
"Now I got you cornered in this storage room so I can kill you right here" Lancer said but Shiro has something in store for him, he points his Advent Deck at the mirror that was in storage room than slip on his belt buckle.
"Are trying to look cool when you die?" Lancer asked after seeing the cool belt buckle thinking Shiro is only trying to look cool after he kills him.
"Kamen Rider!" Shiro morphs into his Dragon Knight right in front of Lancer.
SWORD VENT
Shiro grabs his Broadsword ready for his battle against Lancer who seem impress of what he just witness.
"I don't know the property of your armor and sword but I can use a challenge from an opponent who can stand up to a servant.
"I have clue what you mean by servant but if you insist on that challenge I'll give you one Lancer, oh I overheard the other guy in the red coat call you Lancer", unknown to both of them as they step outside the strange circle begins to glow very bright but both combatants are too occupied to even notice.
An armored figure resembling a knight with a sword emerges from the circle than the light fades away. The armored knight looks around than spots Lancer and Shiro in battle, Shiro loses his Broadsword when Lancer hits his right hand with his Staff but Shiro was able to land a dropkick at Lancer's face, then Shiro slips another card into his Gragon Gauntlet.
GUARD VENT
Shiro summons a Dragon Shield but Lancer tackles him which caused Shiro to drop it leaving him defenseless. Lancer lifts up his Staff preparing to impale him on the gut.
"Your sword gone and now your shield gone, time for impalement", Lancer said then brings down his Staff but his gets interrupted by the knight's sword.
"Servant Saber at your service, tell me red knight are you my master?" The armored knight asked then Shiro felt his left hand burning.
"I see, your indeed my master", the armored knight confirms that Shiro is indeed her master and prepares to defend him from Lancer.
"Your so full of surprise kid", Lancer said to Shiro now that he has a servant by his side.
End
Okay Shinji Mato is Kamen Rider Incisor, that means he doesn't have servant Rider/Medusa but Sakura has her but they will be neutral for most part of the Holy Grail War and the battle against Xaviax.