First, good to hear someone likes it. Always nice.
1 - The Zeroth is "real" as far as that concept can be applied to it. Which it really can't, because the Zeroth is the source of existence and non-existence both, and was "there" before them. It is "real". But it also isn't real. Being an omnipotent being that both contains everything and is the source of everything, it simultaneously contains the qualities of being "real" and being "not real". But it is also beyond those labels and restrictions. If that is hard to get your head around, good, it's intentional.
2 - It's descibred as theoretical because it isn't actually clear if it exists or not for most of the series. It's theorised by philosophical Hallows to be the source of Apeiron that they draw on, and that acts as the "life source" of everything, including living things, dead things, inanimate objects, concepts, dimensions, causality and even non-existence itself. Near the end of the series when the characters ascend to the Ur-Reality and learn a bit more about the cosmological lore of the world, it is revealed that the Zeroth does in fact exist, but it is still never revealed whether or not it is actually sentient and alive, or just some kind of non-sentient highest plane of reality that everything else was simply generated from like mass generates gravity.
3 - It is essentially the first, highest level of reality from which everything else stems. The Zeroth is truly boundless, and contains everything. It is free from all restrictions. It is both powerless and all-powerful. It is nothing and everything. It is living and dead. To use the example of the omnipotent rock paradox, it contains both the quality of being "unable to pick up the rock that cannot be lifted" and also the quality of being "able to pick up the rock that cannot be lifted". Even the name of "The Zeroth" is a restriction, a boundary, which it is free from, so even describing it like I have is in essence a restriction that does not apply to it.
It's as close as I can get to writing an omnipotent creature as I can.
4 - Why are you asking this here instead of on my wall on the other wiki?
Machen Meines Leben basically lets the user re-write themselves. So he used it to, over the course of the war, gain abilities and weapons such as ECD (replaced God Hand, granting timestop and time travel), Gram (a demonic sword equal to Excalibur), Andreis Amarantos (rendering him unable to be harmed except by beings or weapons containing Divinity), God Hand (got it back, giving 12 lives and inability to be harmed in the same way twice), Kazikli Bey (allowing him to summon branches to impale people), Independent Manifestation (letting him create puppet bodies with all his abilities anywhere throughout time and space, as well as making his consciousness omnipresent), Independent Action (letting him survive lethal wounds), Battle Continuation (letting him survive lethal wounds even more), QGG (letting him reset time to the start of the battle) and a shit-load of other abilities that basically make him nigh-impossible to ever put down.
His most notable ability though is Patchwork Soul, which is what happens when you merge a bunch of reality marbles together and start combine that with magical analysers and duplicators.
- Patchwork Soul: World of One Thousand Phantasms: is the manifestation of the constant re-writing and additions Ruler has made to his own soul to grow stronger. It has numerous abilities taken from different abilities he wrote into himself. By deactivating and reactivating the ability, Ruler is effectively able to teleport around the world by choosing a new location to enter the Marble. Finally, Patchwork Soul is not an actual Noble Phantasm - rather it is the collection of Noble Phantasms that Ruler wrote into his being, and he is just as capable of using them all separately as he is using them all at once. Additionally, all Ruler's characteristics are present within Patchwork Soul as it is the projection of his soul (although characteristics of Patchwork Soul are not always preset within Ruler). Additionally, due to Saber's wish to Akasha, Patchwork Soul is surround by infinite further copies of the Marble surrounding the original, making it impossible to enter or exit the Marble conventionally.
Ars Paulina – the original ability that Ruler wrote into his existence. This phantasm creates a workshop outside time and space (so it requires either invitation or special abilities to arrive at, let alone get in) and also lacks a concept of death, allowing Ruler to resurrect any killed there (including himself automatically) as long as he still has mana. Additionally, seeing as it the marble is already outside space-time, it negates all abilities based around being outside or "transcending" space-time, including TTBB. Finally, Ruler can decide its position and passage through space-time, allowing him to control how much time passes in the marble relative to proper space-time.
Aestus Domus Aurea – The manifestation of the glorious golden Colosseum Ruler created within his Reality Marble. Enemies within slowly have their stats lowered, and Ruler’s weapon becomes wreathed in flames with the intensity of Mount Vesuvius's eruption. Ruler can freely reconfigure the shape and function of the buildings in the Colosseum, allowing further customisation. Additionally, it is only possible to exit (either the Colosseum or the entire reality marble) upon Ruler’s death or with his permission.
Nameless Forest – The enemies within will slowly have their mind and memories erased, and when they no longer have a mind, their existence will be erased as well. This memory loss and erasure effect is not active within the Colosseum, although the memories do not return either. Should one read their name while within, this effect is nullified, but it is impossible to recall the name from memory alone, requiring it to have been written down somewhere prior to entry.
Kazikli Bey – A copy of Lancer of Black's Noble Phantasm. It was slightly modified due to the differing circumstances of their legends - while Vlad III impaled his foes on stakes, Ruler impaled them on the branches of trees. As such Ruler's version allows spontaneous growth of trees and tree branches from the ground or trees that attempt to impale foes with their branches – upon contact with an enemy they are conceptualised as having already pierced them through the heart, making armour or toughened skin useless. It can only be used to its fullest effect within the marked territory (Patchwork Soul), although Ruler can also summon these branches from inside his own body even while outside of the marked domain. The amount he can summon is directly dependent on his own mana reserves, which is large enough for him to summon and control well over 50,000 branches at once with ease. He can also summon these branches from any point in his own body, which can be used as an effective surprise attack.
Prelati’s Spell Book – conceptually implanted into the Throne at the top floor of the colosseum. It’s magical reactor grants Ruler infinite mana while within, and fuels the other functions of the location. Additionally, by pressing a button on the Colosseum throne, endless hordes of water demons (all comparable to an E rank servant) can be summoned into the arena and the forest beyond. Additionally, Ruler is capable of summoning it directly from the Throne to his hand, although this also removes the infinite mana effect it grants to the rest of the Marble, making it only a matter of time before the World crushes the irregularity now there is only Ruler's finite mana to sustain its existence.
The King's Glass Game - a copy of Caster's ability The Queen's Glass Game. This ability allows Ruler to reset the conditions of the battlefield and fighters to their condition at the start of the battle through a mixture of reality warping, spatial manipulation and time manipulation. However, this ability can only be used within the confines of Patchwork Soul (although secondary bounded fields and reality marbles within Patchwork Soul still qualify as "within the confines")
Sword of Paracelsus - conceptually implanted into the Throne. Like a quantum processing unit for magic, it will analyse any type of magic (including the magic within equipment type Noble Phantasms) to enter the throne and replicate it. As the throne acts as the heart and brain of Ruler's world, at its very centre, the effects of any magic analysed can now be replicated throughout the entire world. Additionally, Ruler is capable of summoning it directly from the Throne to his hand, although this also disables all effects it is analysing and replicating throughout the Reality Marble (all effects listed below).
Avalon - Gives the environment of Patchwork soul (and Ruler while he is inside it) Low-Mid regeneration, allowing any damage to the environment to quickly be repaired. Additionally, by placing his hand on Avalon's engraving on the armrest of the Throne of the Golden Colosseum, the colosseum gains the protection of Avalon's bounded field "absolute defense" and becomes an impenetrable fortress that can resist all attacks, although the Nameless Forest does not gain this protection. The Throne where Avalon is implanted acts as the core of the world that must be destroyed in order to do permanent damage to the world - however even if the throne is destroyed, this only removes its infinite mana, regeneration, ability analyzing and absolute defense, and Ruler can still maintain the other functions of the world such as Kazikli Bey, Aestus Domus Aurora and the Nameless Forest as they are linked directly to him rather than to the Throne. Unlike other items implanted inside the Throne which are replicas created via Marchen Meines Leben, the Avalon implanted is the real and original Avalon, found by Ruler with the use of Sha Nagba Imuru and Enfer Chateau D'lf and implanted. However, this means that he cannot summon it to himself, nor use its abilities without the Sword of Paracelsus.
Akhilleus Kosmos - a copy of Achille's divine shield, when this Noble Phantasm is conceptualy implanted in the throne, it gives the entire reality marble the durability and strength of the World, meaning that only anti-world Noble Phantasms can damage it. Additionally, Ruler can summon the shield to himself and use it to block attacks, although this disables the World Protection of the Reality Marble until Ruler can return it to the Throne.
The Mist: Ruler can summon a thick black smog anywhere within his Reality Marble. Anything that enters loses its sense of direction, making it nigh-impossible to find a way out of the mist or aim attacks while within. Additionally, beings around his level are slowed (Agility Rank Down) while beings well below his level will choke and slowly die on the corrosive fumes, and Ruler is extremely difficult to see in this mist, gaining increased stealth. Finally, Ruler can summon the lantern that is the ability's source to himself from the Throne and use it to personally summon and control the Mist around him, although this disables the Mist that is otherwise omnipresent throughout the Reality Marble of the Reality Marble until Ruler can return it to the Throne.
He also has God Father's Authority, which is basically BB's Earth Mother's Authority, except only over Patchwork Soul rather than earth.
A few other noteworthy points would be that Ruler has had his existence confirmed by Akasha negating any buffs, debuffs or other alterations to him, SNI, a version of GoB called Ruler's Treasury which is a high quality dumpling delivery pocket dimension, and, most importantly of all, Neverland Overdrive!!!
Using SNI and NO together he can create the SNITV, a device that allows anyone to view things normally only visible within an SNI user's mind as if they were watching a movie. It can also give descriptions of anyone and anything they want.
Along with that he currently has two contracted servants, and if war 2 ever ends will likely get a third. Though they're total fodder characters, I mean it's just an immeasurable speed EX ranked weakling, and a weakling who can disorient you, hide themselves, turn invisible, and one hit kill you all from kilometers away.
Well, actually you'd be able to get away from him for a time by hiding somewhere in imaginary number space outside space-time. But SNI combined with ECD means he'll know where you are, and be able to get to you eventually.
I'm asking this out of curiosity more than anything else, but I've seen you in at least five different Dresden-related VS threads and you seem to be one of the only people here who knows a good deal about the character and his verse. I figured it'd at least have a passing mention in that section.
I'm personally not as familiar with the verse as I might seem. I only ever got to the eighth book before fell off for reasons I can't remember, and that was at close to nine years ago. I was impressed with your knowledge on the character, though.