Sieg was created by Yggdmillennia as one of their many homunculi suited to various purposes. Initially kept in a magical energy supply tank devised by Gordes Musik Yggdmillennia to grant energy for Servants and was originally known as Homunculus (ホムンクルス, Homunkurusu?), he was one of many allowed to be used by Caster of Black for usage as harvesting materials for his golems. Due to his unexpectedly high quality Magic Circuits, he was thought to be a good choice for Caster's Golem Keter Malkuth.
A standard characteristic of Einzbern Homunculi, Sieg's eyes are the same deep, dark red of polished, perfect rubies. His hair is brown, though it appears to darken ever so slightly as he 'ages'. At the outset, Sieg's physique is quite slender and frail, like a newborn infant, and equally as weak. His standard clothing consists of a black waistcoat, white shirt, black slacks, and a pair of black leather penny loafers.
After obtaining the heart of Saber of Black, his physical appearance changes slightly to mimic that of Saber. While his hair only darkens (and shortens) slightly, he grows far taller than he originally was, and the frailty of the past was replaced with a slender-but-hardy build much more suitable for fighting in a Holy Grail War. He also swaps out the loafers for a pair of half-boots.
"Perhaps we don't deserve such a thing as free will. I don't really know if what I've done till now is right or not. But, even if there's no rest beyond this... Even if there's only despair beyond this... At the very least I want to walk my own path! We don't ask for salvation, either! But I want at least the freedom to choose!"Sieg comes into consciousness without anything to form a personality. He is scared of everything but himself, believing to be nothing. He calls himself transparent and colorless because he possesses nothing and had received nothing from his birth.
After escaping and receiving the hero Siegfried's heart, he becomes notably more selfless and brave as he continues to develop. Of his own volition he decides to forsake a life of happiness for himself and instead aims to fulfill the desperate wishes of his brother and sister homunculi who would die if nothing was done to save them. Eventually, he willingly becomes a participant of the Holy Grail War for their sakes as well as to save Astolfo who had previously saved him. Due to his young age, he is still very naive and clueless about manners and how the world works though overall he is usually very calm and logical, being is able to pass as an eccentric but otherwise normal human being in a very short amount of time. He can at times display a somewhat cold and blunt attitude, particularly towards Gordes, though he does still express gratitude towards him for creating him and his brethren.
He is surprisingly vengeful and drops his usually stoic demeanor when those he cherishes have been harmed and swears to kill Assassin of Black and recklessly attacking the Servant when he sees her mist has gravely injured and taken the life of one of his siblings. Similar to Siegfried he places little value on his own life, and comes to view himself as something that can be used to save and help those around him, causing him to make absurd, unreasonable and reckless choices, though both Ruler and Laeticia eventually encourage him to start considering his own value more. After their final encounter with Assassin of Black and witnessing her along with the children of Scotland Yard's horrific pasts, Sieg's innocent belief of humans being inherently good creatures crumbles, leading him to began to question humanity's nature as a whole. While he takes Ruler's advice on not giving up humans to heart, and thinks over the opinions of several others on the matter, he ultimately seeks his own answer to how he views humans and life as a whole.
The reason Sieg acted for the sake of humanity at the end naturally wasn’t for humanity’s sake in and of itself. In the first place, Sieg hadn’t experienced enough to completely believe in humanity. However, Jeanne d’Arc waged her life to win the future. It is because he saw that and wished to “become her strength” that he acted, a greatly personal desire.
- Jeanne d'Arc
- Sieg feels deep admiration for Jeanne and also wants to protect her. Later Sieg and Jeanne met again in the Reverse Side of the World and Jeanne confesses her love to Sieg, saying unto him, "I am in love with you."
- Astolfo is Sieg's friend and savior. He greatly respects and cherishes Rider. While Rider thinks of himself as weak Sieg truly believes in Astolfo and his strength. To him, Astolfo is truly an amazing person. Though his wild antics and carefree nature can occasionally wear on Sieg's nerves.
- Jack The Ripper
- Amakusa Shirou Tokisada
Sieg, originally just an unnamed homunculus, first begins to gain sentience around the time the Black Faction has summoned all of its Servants. Originally, he is conscious without the ability to form thoughts, only a weak "instinct" protesting about a great pain. Without the ability to form thoughts or have recognition of anything, he cannot assert himself or clearly be called "alive." Simply by existing, he is able to receive "information", leading to "time" to process the information that eventually creates "knowledge" within him. He becomes conscious, and he is able to realize the simple fact that he is a living creature. The cycle of learning begins to repeat at a great speed, bolstered by his Magic Circuits. He recognizes many beings, including humans, homunculi, and Servants. The humans ignore him, the homunculi, his comrades, view him with faint emotions, and the Servants, monsters, display a wide variety of expressions.
There is no great change in his situation with the acquisition of knowledge, but he slowly begins to organize it within himself and begins to feel strange with the more information he obtains. Without realizing it to be fear in wanting to turn away from that which is in front of him, he cannot even understand it being an act of cowardice because he has yet to understand the idea of courage. After the scouting of Kairi Sisigou and Saber of Red leads to battle with several of Caster's golems, Caster and Roche Frain Yggdmillennia appear before Sieg, discussing the process of inserting Magic Circuits into the golems. Identifying them by their "codes", names, Sieg is able to recognize that they have appeared before him numerous times, and using his information, he is able to determine the insertion of Magic Circuits equates to the destruction of that which is consumed to supply them. Having not previously understood death, he becomes scared upon drawing the conclusion that destruction equals death.
As he is selected along with two others for Caster's usage, the part of him that had been scared clearly notes that he will soon die. Though he initially believes that there is no recourse, he decides to act due to being able to do what the other homunculi cannot, obtain information, think, and fear the conclusion. With the coincidence of obtaining an identity along with the coincidence of being chosen to die, his fate begins to move as he moves his arm for the first time in his life. Affirming his situation as he attempts to move, he makes both his hands move to beat against the reinforced glass. Realizing the futility in trying to break it physically, he scans his Magic Circuits to work a spell that weakens the glass enough for him to escape, breaking it and allowing him into the world from which he had been isolated. Injured from the glass, he removes his breathing apparatus and takes his first breath.
He quickly reminds himself that escape from the glass was only his initial goal, quickly seeking to escape. The ability to stand was not imbedded into his functions, so he can only fall and feebly craw along the floor. Slowly managing to stand, he is filled with great pain as he begins his first steps. He does not know his path, only knowing that he will die if he stays, and he can only walk forward with great trepidation of further pain as he ignores the "whispers" of the homunculi behind him. With skin as soft as that of a newborn, simply walking is enough to bloody his feet as he searches for a destination. Thinking himself to be a meaningless existence as his weak body struggles along, he can only believe that he will die without meaning in the same way he was born without meaning.
He pauses in confusion as he realizes Rider of Black has come before him, unable to move out of fear. Soothed by Rider's concern, he recognizes Rider and unconsciously mutters for Rider to help him before fainting. Before fading out, he only wishes that he will continue to be alive. Rider decides to help him, bringing him Archer of Black's room to hide him from Caster's pursuit. Archer realizes the situation, letting them in and preparing to look him over due to his expertise on medicine. He states that Sieg overused his circuits and tore through his veins in destroying the glass and further collapsed from exhaustion. He tells Rider of Sieg's physical condition and short lifespan, and Rider affirms that he will keep helping him until the end, as he would not be able to survive on his own.
Sieg awakens during their conversation, so he gets up at Rider's prodding. Extremely nervous, he is unable to understand Rider's meaning as he asks about helping to grant Sieg's wish. As he thinks about it, he believes a powerless being with no history has no right to have a wish in the first place, having given up such a right in the first place. Although he believes he does not deserve such a thing or that it will be granted, he asks Rider to save him. He is shocked when Rider agrees immediately, but becomes moved enough by Rider's innocence to have no doubt in his words.
He clashes with Saber of Red during a large battle. She calls him a fake Heroic Spirit, and he acknowledges that he cannot match up to a proper Heroic Spirit. In order to save his comrades who were left behind, he decides to utilize his Saber's Noble Phantasm, Balmung, clashing with her Clarent. He does not care about winning or losing, only that it is a necessary action. He who does not have a life in the first place cannot be said to be risking his life. Red Saber comes out victorious, but only due to the special properties of the weapons and the distance from which they attacked. It is possible utilizing Balmung even a few steps closer may have changed the outcome. She is infuriated because he still lives, and moves to finish him.
Manaka Sajyou in her dimensional travel saw a detached and kind dragon (孤高なりし優しき竜, kokō narishi yasashiki ryū?), waiting for another for a very long time in the Reverse Side of the World. Manaka finds the dragon's appearance to be beautiful, but the dragon does not respond to Manaka, as both of them saw the end of the world.
He possesses first-class Magic Circuits. Sieg is a being whose purpose was to have Magic Circuits as the foundation of his body, so his ability to comprehend information is great. He is able to go from being less aware than a baby to gaining knowledge at an abnormal speed in a span of days. He is made to take in mana from the atmosphere and provide it to Servants, and he is able to manually cut the link upon gaining intelligence. Instinctively knowing magecraft, he is able to use the spell "Logic path/open (理導／開通, Ridō/kaitsū?)" to wish for a result of "destruction" on the glass holding him, causing his magical energy to transform it in a way for the least "destruction" required. Able to understand the mineral the glass is constructed from, it becomes as brittle as a weak piece of wood. When Sieg tries to protect himself from Gordes, he uses this technique to defend himself. His palm became the barrel of a gun - the sheath of a sword - and what it fired was a bullet or perhaps blade that would not only destroy Gordes' arm, but mercilessly devour his heart.
Unlike regular homunculi built to be functional, perfect lifeforms, he possesses many physical defects, and while his circuits are first-class, his body is not able to utilize them without failing. Meant only to supply magical energy and not act as a fighter, he is physically weak and will only live three years at most.
After gaining Saber of Black's heart, his appearance physically changes and he gains a stronger constitution which leads Rider of Black to claim he can live for more than 100 years. He has special black Command Seals which appeared on the back of Sieg's left hand known as Dead Count Shapeshifter: Dragon Revelation Command Spells (竜告令呪, Ryū Tsuge-reiju?) which allows him to take the form of the Heroic Spirit Siegfried for 180 seconds (3 minutes). He can only take form using the Command Spell for a limit of three uses. However they can be used as normal Command Seals, but does not use them that way towards Rider.
His parameters, experience, technique, personal skills, Noble Phantasms all are replicated perfectly but he cannot match a true Heroic Spirit. His usage of Balmung does not appear impeded by this. He requires adequate magical energy stored in his body and the use of a Command Spell to take on Saber's form.
Using Balmung is enough to deplete his reserves completely, causing him to lose Saber's form even as his magic circuits desperately cling to "remain as Saber." His armor and Noble Phantasm disappear, causing Saber of Black to vanish from the world. The process brings extreme pain to his flesh, bones, and nerves, and he loses any ability to move or retaliate. It is possible to transform again, but his body cannot endure to do so consecutively.
However, after getting revived by Frankenstein's lightning imbued by her will a piece of her is reborn inside him it ceased to hinder him. Later granting him the perpetual motion machine ability of Bridal Chest, he used it, during his battle with Karna and later Shirou, Sieg managed to use Balmung so many times consecutively only because he continued to instantaneously pull out the sword’s power while replenishing his mana with “Galvanism”. The Servant version of Siegfried cannot instantly replenish the mana he expends, so his sword’s accumulation of prana is overwhelmingly faster than that of an average Anti-Army Noble Phantasm, though still not as fast as Sieg When Sieg battles Lancer of Red, he is able to use Balmung together with Galvanism to great effect and is able to activate Balmung consecutively. After witnessing two back-to-back attacks on the level of Brahmastra Kundala, Lancer decides that there is only one way to win and uses Vasavi Shakti. Balmung would have been penetrated in only two seconds, but Sieg uses a command spell to boost it, allowing it to reach an equal footing with Vasavi Shakti. It becomes a battle of will from this point on, but since Sieg's opponent was Karna who was famous for his indomitable will, Vasavi Shakti was able to break through Balmung.
Before the killing blow he was saved by Astoflo with Achilles' shield Akhilleus Kosmos. He was closer to the real form of Siegfried than even the heroic spirit copy. The living Siegfried, on the other hand, had his inborn disposition combined with the transformation of his heart into a Magic Core due to being bathed in and drinking a dragon's blood, so he could draw forth magical energy and fire the slash wave even faster than Sieg. Unfortunately, the moment he was summoned as the Servant Saber, that special characteristic of his was highly degraded.. Later he used a weakened version of Blasted Tree against Shirou in their final fight as his trump card.
Also displaying the ability to transform into the dragon Fafnir due to him having Siegfried's heart giving him dragon blood as he used this to carry the Greater Grail to the Reverse side of the world where phantasmal beasts go where no human can venture so the wish for humanity does not occur as phantasmal beasts are invalid targets. As a result of the transformation he lost his physical form and his final state is that of his soul.
Creation and ConceptionEdit
Yuuichirou Higashide said that everything started from him. When he was discussing wild ideas with Kinoko Nasu, Higashide said "his Chest will glitter brightly, three full times!", to which he found it too stupid so he removed it when he was writing the story.
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6
 Fate/complete material IV: Extra material - Fate/Apocrypha - Siegfried, p. 296-297
Siegfried, the Dragon-Blooded Knight
He is the hero portrayed as the main character of the German Nibelungenlied epic. Prince of the Netherlands, he wields the precious sword Balmung which he received from the Nibelungen family, and has fought in many campaigns and adventures. His most well known feat is killing the evil dragon Fafnir. He then bathed in the blood of the dragon, and has obtained an invincible body. His personality is truly that of a noble knight. But because he never speaks a word, it is unknown what he really thinks.
- Class: Saber (Rider)
- Source: Nibelungenlied
- Region: Germany
- Alignment: Chaotic Good
- Sex: Male
- Height: 190cm
- Weight: 70kg
- Armament: Sword
Siegfried has been in battles ever since he was a young man, and he has gained an invincible body from his victory over Fafnir in battle for the treasure of the Nibelungen family. But when he bathed in the dragon's blood, a tree leaf stuck to his back, making it his one weak point. Adding to the growing ranks of the Burgundians, he brought them many victories, and married Kriemhild, sister of the Burgundian king, accessing the throne of Netherlands. But after a trick to marry the Burgundian king to the queen of Iceland, Brünnhilde, he was assassinated by a vassal of the Burgundians who struck him on his weak point. This connects to the revenge tragedy of his wife Kriemhild for the murder of her husband in the later half of the tale.
- STR: B+
- CON: A
- AGI: B
- MGI: C
- LCK: E
- Noble Phantasm: A
- Class: Saber (Rider)
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13
 Fate/Apocrypha material - STATUS: Saber of Black, p.018-019
Master: Gordes Musik Yggdmillennia
True name: Siegfried
Alignment: Chaotic Good
Noble Phantasm: A
■ Magic Resistance: -
As compensation for obtaining Evil Dragon's Blood Armor this is lost.
■ Riding: B
Majority of vehicles can be ridden above average. Magical Beasts, Holy Beast rank beasts cannot be ridden.
■ Golden Rule: C-
A life in which money is fated revolve around.
Due to the Nibelung treasure promised a life untroubled by money, but Luck is Rank-Down.
■ Armor of Fafnir: Blood Armor of the Evil Dragon
Maximum number of targets: 1 person
A Noble Phantasm embodying the story of his bath in the blood of a dragon. B-rank equivalent physical attacks and magic are nullified. Attacks of A-rank and above register as damage after defensive values of an amount equal to B-rank are subtracted from them. If facing a Noble Phantasm used by a proper hero, it gains defensive values equivalent to B+. However, his back, which was not bathed in the blood, does not gain defensive values, and he is unable to conceal it.
■ Balmung: Phantasmal Greatsword, Felling of the Sky Demon
Maximum number of targets: 500 people
A cursed holy blade which had accomplished the feat of dragon slaying.
It also possesses the attributes of its origin, the demonic blade Gram, and will change attributes between holy sword and demonic sword depending on who wields it. The blue jewel of the hilt stores and preserves magic energy (true Ether) from the age of gods, and upon releasing it, emanates a twilight aura. Those with the blood of dragons take additional damage.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7
 Fate/Apocrypha material - CHARACTER Profile: Homunculus "Sieg", p.054-055 [T]
- Age: 0 years old
- Height: 165cm
- Weight: 53kg
- Talents: None
- Likes: None
- Dislike: None
- Image colour: Transparent
- Enemy: enemy: Shirou Tokisada Amakusa
Comment from Yuichiro Higashide & Ototsugu Konoe
Comment from Yuichiro Higashide & Ototsugu Konoe
- Age: 0 years old
- ↑ 4.0 4.1 4.2
 Fate/Apocrypha - Volume 1 - Character Profile: Homunculus [T]
An artificial life-form created using techniques of the Einzberns in order to supply magical energy separately from the Yggdmillennia Masters.
He possesses first-class Magic Circuits, but he's a failed creation from birth.
 Fate/Apocrypha material - Encyclopedia: Sieg [Person's name], p.168-169 [T]
Sieg [Person's name]
The protagonist of the light novel “Fate/Apocrypha”. He was originally a homunculus made by Gordes to supply prana, created not to think anything and fated to die after having his prana wrung out by the Servants, but… Almost all details about him were depicted in the novels through the entire course of his life. After all, he has virtually no past to speak of.
Not only that, his life was set to be limited from the beginning as the premise of his birth. Even if he had thought of living a respectable life, he would only have live three years at the most. It’s precisely because of this that he continued to choose absurd, unreasonable and reckless choices for the sake of “what he thought he should do”.
Even after he acquired greater longevity, that aspect of him didn’t change. The reason Sieg acted for the sake of humanity at the end naturally wasn’t for humanity’s sake in and of itself. In the first place, Sieg hadn’t experienced enough to completely believe in humanity.
However, Jeanne d’Arc waged her life to win the future. It is because he saw that and wished to “become her strength” that he acted, a greatly personal desire.
Additionally, his Magic Circuits alone were of such high quality that Avicebron had an eye on him and were in no way inferior to those of Darnic, Yggdmillennia’s head. However, he can only use them to destroy things through Structural Analysis. Even if he had survived, he wouldn’t have had any intention of studying magecraft since he doesn’t have a very positive image of it.
Having transformed into one of the Dragon Kind at the end, Sieg has already lost his physical body. His final state is the form of Sieg’s soul after he transformed by making a wish upon the Holy Grail.
Incidentally, the words Jeanne spoke at the end of the novel made Sieg finally understand the reason why he continued waiting for her all that time. The two of them take being thick-headed to a new extreme!
 Fate/Apocrypha material - Encyclopedia: Dragon Revelation Command Spells [Others], p.176 [T]
Dragon Revelation Command Spells [Others]
Dead Count Shapeshifter. The unique Command Spells engraved on Sieg. They can also be used as normal Command Spells, but there was absolutely no need for Sieg to force Astolfo to do anything with a Command Spell, so he used them all to turn himself into Siegfried. To explain it simply, they basically let Sieg summon Siegfried every time he uses one. The catalyst is Siegfried’s living heart. However, while Siegfried’s body could withstand the dragon blood within it, Sieg’s body can’t. That is reason that the spots on Sieg’s hand where the Command Spells disappeared from turned black. Even after he used them all up, power Sieg obtained from Frankenstein’s “Blasted Tree: Lightning Branch of Crucifixion” managed to barely maintain his human form, but that too was used up when Sieg used this Noble Phantasm at the end.
 Fate/Apocrypha material - Encyclopedia: Saber of “Black” [Servant], p.162 [T]
Saber of “Black” [Servant]
One of the Servants of the Black camp. His true name is Siegfried. He is an undisputed great hero and “dragon slayer” who appears in the “Nibelungenlied”. His tall stature, slender body and tanned-colored skin are proof of him having been soaked in the blood of a dragon. The reason the weak point on his back is exposed is because of a “curse” that forces him to do so. It conceptually prevents him from protecting his back. Even if Siegfried were to be protected by something like a spherical barrier, a hole in it would definitely open facing his back. However, there aren’t many heroes who possess the skill to pull off the tricky feat of aiming for Siegfried’s back while fighting him in the first place.
Just as the impression of his face gives off, he is reticent, but his bearing, which overflows with dignity, makes him seem well-bred. He is the type to talk with a simple, unsophisticated tone and hold back his words to the absolute minimum needed. That is the foundation of his personality, and it deepened the antagonism between him and his Master Gordes.
Siegfried’s legend came into existence around the 5~6th century and spread to many lands. At nearly the same time as the “Nibelungenlied”, the story of the hero Sigurd, the “Volsunga Saga”, came into existence. Wagner’s opera “Der Ring des Nibelungen” is a masterpiece work that compiles these legends together.
In the light novels, Siegfried as he was portrayed in the “Nibelungenlied” forms the basic essentials of his character, and he only knows about the Norse Valkyries from second-hand knowledge.
With him possessing the noble lineage of royalty, being known for various his adventures and heroic tales and having met a tragic end, there are few heroes who are as heroic as him.
But it is precisely because he is such a heroic hero that he was unconsciously burdened by binds. A hero acts out of the supplications of the people, and therefore should not act without being asked. This is because a hero is such a being. Because they possess overwhelmingly immense power, they must not act out of their own will and try to grant their own wish. A hero is a being that fulfills the wishes of others, and must not ever tread any further than that.
When his wife and the wife of his brother-in-law wounded each other’s honor and a collision between them became inevitable, he once more granted everyone’s wish. He thought that it would be resolved if he, the cause of it all, died. In the end, it called forth even more tragedy, so it seems the curse of the Rhine gold took effect perfectly.
As a Servant, he is basically hard, solid and tough. “Armor of Fafnir: Blood Armor of the Evil Dragon” blocks all regular attacks up to B rank and all Noble Phantasm attacks up to B+ rank and, in addition, “Balmung: Phantasmal Greatsword, Felling of the Sky Demon” unleashes a wide-range attack that displays its true worth against an army. The blue jewel encased in the hilt of the sword contains prana from the Age of Gods, and it is possible to pull out the sword’s power to the maximum with just small quantity of it. During his battle with Karna, Sieg managed to use the Noble Phantasm so many times consecutively only because he continued instantaneously pulling out the sword’s power while replenishing his prana with “Galvanism”. The Servant version of Siegfried cannot instantly replenish the prana he expends, so his sword’s accumulation of prana is overwhelmingly faster than that of an average Anti-Army Noble Phantasm, though still not as fast as Sieg.
In the initial plans of the Yggdmillennia team, Siegfried would go out to the front lines and receive the attacks of enemy Servants as Vlad III’s protector. Vlad would be positioned to control the battlefield with “Kaziklu Bey: Lord of Execution”. Jack the Ripper would kill the enemy Masters and cause chaos in the enemy’s rear guard along with Frankenstein. Astolfo would guide the golems and control the situation with Avicebron, while Chiron would act as support by shooting at areas where a hole in the enemy lines could be made.
It was truly a perfect formation as an academic theory, but they were forced to tearfully change tactics due to Siegfried unbelievably leaving the battlefield before the war actually began.
 Fate/Apocrypha material - Encyclopedia: Phantasmal Greatsword, Felling of the Sky Demon [Noble Phantasm], p.179 [T]
Phantasmal Greatsword, Felling of the Sky Demon [Noble Phantasm]
Balmung. The Noble Phantasm of Saber of Black, Siegfried. The Nibelungs, a tribe which lived in an underground country, requested that Siegfried fairly and impartially divide up and distribute their treasure, and he accepted the request. Balmung was planned to be given to him as payment for this. However, two kings felt that the allocation of treasure was done unfairly (both kings felt they were being treated unfairly, so it’s highly possible that it was actually divided up fairly without Siegfried favoring either one) and fought Siegfried, but he killed them in return.
The remaining treasure which no longer had an owner became Siegfried’s, and Balmung also became his weapon. He wielded Balmung in every battle after that. It is also said that he won in the battle against Fafnir thanks to Balmung.
It is a sword of twilight that has reached A rank and possesses the quality of both a holy and cursed sword. Perhaps because it was owned by a king, it specializes in fighting against armies, shooting off a semi-circular slash wave. The blue jewel attached to the handle stores True Ether to use as a boost when activating the Noble Phantasm.
Now then, it does have a fast activation rate for a so-called beam weapon, but in a comparison of speed, Siegfried when he was alive was the fastest in activating it, with Sieg being the next fastest and the Servant Siegfried being the slowest out of them.
Sieg possesses the “Galvanism” ability, which the Servant Siegfried does not have, and can draw out the needed prana all at once when activating the Noble Phantasm. The living Siegfried, on the other hand, had his inborn disposition combined with the transformation of his heart due to being bathed in and drinking a dragon’s blood, so he could draw forth prana and fire the slash wave even faster than Sieg. Unfortunately, the moment he was summoned as the Servant Saber, that special characteristic of his was highly degraded.
 Apocrypha material - Sieg/Siegfield, p.006-007 [T]
Talk about Siegfield
Higashide: This the instant-Servant and homunculus, Sieg-kun. When I think about it, everything started from him. This is bit of a digression, but when we were talking about wild ideas with Nasu-san, I said, “His chest will glitter brightly, three full times!”, but when I was seriously writing the story, I found it too stupid so I removed it.
Konoe: Sieg-kun in his transformed hero form will be in the highlight scene of the final fifth volume as well! Please look forward to it! And each time Siegfried’s armor appears in an illustration, I receive no mercy as my arm dies due to the miraculous number of lines I have to draw. Good heavens!
Talk about Siegfield