Knight Classes: Sabers (A-F | G-M | N-Z) | Archers (A-C | D-M | N-Z) | Lancers (A-F | G-M | N-Z)
Cavalry Classes: Riders (A-F | G-M | N-Z) | Casters (A-F | G-M | N-Z) | Assassins (A-F | G-M | N-Z) | Berserkers (A-F | G-M | N-Z)
Other Classes: Extra (Rulers | Avengers | Moon Cancers | Alter Egos | Foreigners) | Beasts
Unplayable and Arcade Exclusive: (Unclassed | Arcade Exclusive)
Other Notable Characters: Chaldea Security Organization | Villains (Observer on Timeless Temple Villains | Epic of Remnant Villains | Cosmos in the Lostbelt Villains | Crypters | Foreign God and Forces | Lostbelt Kings | Event Villains | Interlude Villains) | Other Characters
There are additional Classes and designations that do not fall under the seven "regular" Classes summoned as part of the Holy Grail War ritual. These fall under the umbrella term of "Extra Classes", and are typically only summoned under extraordinary or taboo circumstances. As the Grand Order and the FATE summoning system do not operate under the rules of a Holy Grail War, such Servants are far more common during the events of Fate/Grand Order.
While many Extra Classes exist, like Gunner, Faker, Voyager, Watcher, Saver, or Funny Vamp, only seven have appeared thus far in Grand Order: Shielder, Ruler, Avenger, Moon Cancer, Alter Ego, Foreigner and Pretender, the last two of which make their introduction to the franchise here. The classes of Ruler, Avenger and Moon Cancer make up their own class triangle with Avenger beating Ruler, Ruler beating Moon Cancer, and Moon Cancer beating Avenger, while Alter Ego, Foreigner and Pretender also make their own class triangle, with Alter Ego beating Foreigner, Foreigner beating Pretender, and Pretender beating Alter Ego. Shielder, currently exclusive to Mash, exists outside all class interactions and thus hits for and receives neutral damage from all classes.
Pretender (UNMARKED SPOILERS)
Introduced in Cosmos in the Lostbelt, the Pretender class is defined as those who would deceive and mislead others to accomplish their deeds with such skill and deception that their guises would be just as powerful as the deceiver or even greater. These Heroic Spirits are those who use a role and are opposed to neither man nor monster, but the World itself with their impersonations.
Pretenders are strong against Alter Egos, but weak against Foreigners. They deal extra damage against Sabers, Archers, and Lancers, but deal half damage against Riders, Casters, and Assassins. Pretenders both deal extra damage to and receive extra damage from Berserkers.
- Consummate Liar: The biggest qualification to be a Pretender servant as they have spent their life deceiving and lying to others to the point that they'll even deceive the soul itself.
- Suspiciously Similar Substitute: Pretender shares a number of characteristics with the Faker class introduced in Lord El-Melloi II Case Files. The difference is that a Faker Servant is reserved for those who were body doubles of Heroic Spirits in-life, and have a counterfeit version of that Heroic Spirit's powers as a result with some differences and their own powers mixed in, which they use to trick others into believing they are the real Heroic Spirit and not a double. A Pretender Servant, meanwhile, is one who spends their life tricking and deceiving to achieve their goals to the point that they are able to trick the soul itself until they gain even more power and greater achievements than their real selves had, which shows by their ability to change their Servant Class at any time or assume the identity of a Heroic Spirit that is completely unrelated to them and reap the benefits. Going by the classes' representatives, however, the representative Faker, Iskandar's Shadow, is infinitely less evil than the representative Pretender, Oberon.
ID: No. 316
Command Cards: QQABB; (B)
Alignment: Chaotic Evil
Origin: Literature (A Midsummer Night's Dream), England (Arthurian Legend)
First appearance: Fate/Grand Order (Oberon), Garden of Avalon (Vortigern)
Illustrated by: Chica Umino
Voiced by: Toshiyuki Toyonaga
The king of the fairies in medieval and Renaissance European literature, most famous today for his role in William Shakespeare's A Midsummer Night's Dream. According to Oberon, his wife in Shakespeare's play, Titania, is a purely fictional creation of Shakespeare's.
All that was described above are all but lies when it comes to this Oberon. He is not a Servant from Proper Human History, but an apocalyptic device created by Faerie Britain to destroy itself. He is named Vortigern, a name shared with the uncle of King Arthur, the personification of the white dragon who tried to bring an end to the Age of Man. He had tried to bring an end to the land of fairies in the Great Calamity, but was stopped during that. He was reborn in the Autumn Forest of Wales, where the outsider fairies claimed him as their king, making him "Oberon".
He serves as an ally and the final antagonist in "Lostbelt No. 6: Fairy Round Table Domain, Avalon le Fae", as he is the one behind the threat of the planet collapsing that forced Chaldea to enter the Lostbelt.
- Affably Evil: Despite his oddities as Oberon and the sheer horrific brutality of him as Vortigern, he sincerely remains polite all the way up to and including his demise towards Chaldea and even wishes them luck when he's finally beaten by them, making him miles more genuine than the significant majority of the fairies of the Lostbelt.
- Alternate Self: Played with. This "Vortigern" and Vortigern of Proper Human History are both technically embodiments of their Britain's will who take monstrous forms relating to dragons and darkness, but this "Vortigern" as a person is not related to Altria or Morgan like the Proper Human History version was. However...
- Ambiguous Situation: ...The story never spells out exactly if the Vortigern summoned in the Lostbelt is truly a "Vortigern" unrelated to his Proper Human History self. Though it is stated multiple times he is a Servant born of Faerie Britain and not Proper Human History, there has been so much wire-crossing between the alternating histories in Faerie Britain due to Morgan's meddling that it's entirely possible PHH Vortigern got caught in the mess and altered like Kadoc's version of Anastasia, not helped by the Welsh Faeries potentially altering him a second time into being Oberon. While the possibility definitely exists, it's never explicitly stated, and given Oberon-Vortigern's nature the ambiguity is likely intentional.
- Animal Motifs:
- Moths. He has moth wings, a moth companion named Blanca, and sometimes puts on a cap with moth antennae accessories.
- When his true self is revealed, the motif swaps over to dragonflies as a play on how he's both an insect fairy and draconic as Oberon Vortigern. He has dragonfly wings, and transforms into a massive dragonfly for his Noble Phantasm.
- In a bit of a carryover from his Proper Human History counterpart, Dragons, in a roundabout way. His Human History self is the incarnation of White Dragon of Britain, destined to destroy human civilization on it. This Lostbelt incarnation has dragonfly wings, and Lie Like Vortigern transforms him into a huge worm... or in other words, a huge wyrm.
- Anthropomorphic Personification: If Proper Human History Vortigern was Britain's will to stay in the Age of Gods, then Oberon Vortigern was Faerie Britain's desire to self-destruct and punish the faeries living on it for their sins and how they betrayed Cernunnos to build it. Vortigern says he would never have been born to destroy the land if Morgan hadn't tried so hard to save it against her given purpose.
- Arch-Enemy: Much like how Proper Human History Vortigern considers Altria as his greatest obstacle in preserving the Age of Gods and killing the humans of Britain, this Vortigern regards Morgan, who tries to preserve Faerie Britain against the wishes of the island itself, as his enemy, especially during his time as King of the Mors. Likewise, Morgan also sees him as a personal threat, and expresses her displeasure to him in a voice line. That being said, see It's Personal below.
- Arc Villain: Ultimately the real antagonist behind the sixth Lostbelt, as he was secretly behind agitating the Mêlée à Trois between the factions in hopes of destroying the Lostbelt so he could escape to destroy Proper Human History itself. Indeed, it's neither Morgan nor Cernunnos but rather Vortigern that is the true nature of the collapse Sion detected, with the SHEBA lens predicting that he will emerge victorious, suck up Faerie Britain into the Hollow Worm, break free of the British Lostbelt, and then repeat the process with the rest of the planet.
- Attack Its Weak Point: Despite the Hollow Worms enormous size and destructive potential, it requires Vortigern to direct its movements and actually suck in things through its mouth into its Bottomless Pit insides. Ergo, if he is neutralized, then the Worm will stop moving and cease to be a threat.
- Ascended Meme: His Sleep-Mode Size is both a Call-Back to the April Fools' Day card art of Queen Medb (who has a connection to fairies) and the classic meme of putting other Servants in her comfy looking cloak.
- The Bad Guy Wins: In the absolute Mêlée à Trois of different villains that is the Faerie Britain Lostbelt, Oberon-Vortigern's purpose of wiping it out ends up trumping all of the other villains, with the Hollow Worm being seen tearing the island to pieces. The only reason he really "lost" is because his plans include destroying Proper Human History as well. To be more precise, Vortigern's desire to wipe out the British Lostbelt succeeds, but Oberon's desire to wipe out the Proper Human History fails. One of his Third Ascension My Room lines has him gleefully rub this fact in the faces of the Lostbelt Kings.The Lostbelt Kings? Of course I respect them! After all, each and every one of them yielded to Chaldea, did they not? Humans are amazing! Just as I expected of the kings...ah, but don't lump me in with that bunch, okay? Those guys are miserable losers. I, on the other hand, am a winner who has fulfilled his purpose.
- Badass Cape: As can be seen in his NP, his cloak appears to be made from butterfly wings. Or to be more appropriate, ripped off fairy wings. It'd be incredibly fitting considering his role.
- Beauty Is Bad: The fairies mistake Vortigern for Oberon due to how pretty he is, but by the end of the Lostbelt it's revealed he's one of the Six Calamities the Child of Salvation is meant to slay, the Insect of the Abyss.
- Becoming the Mask: Downplayed. After recovering his identity, Vortigern settles into continuing the guise of Oberon to deceive Chaldea and achieve his ends, but he does still like them. Not enough to avoid killing them, however.
- Big Creepy-Crawlies: When he's acting as Oberon, he usually sticks to butterflies, moths, and other "cute" and relatively normal-sized insects. When the gig is up, however, Vortigern pulls out all the stops and starts summoning all kinds of bugs, including things like beetles, wasps, giant centipedes, and a pillbug the size of a small car. And of course there's the Hollow Worm itself, an "insect" big enough to shatter an entire country with its movements and wingbeats.
- Bishōnen: Despite being unrelated to the Pendragons unlike his Alternate Self, this Vortigern still has natural good looks. This is actually what caused the Welsh fairies to accidentally brainwash him, as he was so pretty that they were convinced he had to be a prince of some sort, thrusting the identity of Oberon on him.
- Bonus Boss: Fully ascending him and completing Avalon le Fae will unlock a interlude where you can face a Shadow Servant version of him. This variant carries a few tricks his boss variant never used in Avalon le Fae, such as using End of a Dream EX before activating his Noble Phantasm, and using his Noble Phantasm even as a Shadow Servant, a feat that Shadow Hassan of the Serenity and Shadow Tamano Cat have used during their boss fights within Camelot and Avalon le Fae respectively. The reward is access to both his Third and Final Ascension arts, alongside his respective lines and access to his second NP Lie Like Vortigern.
- Boss Subtitles: The final battle against him introduces him as Insect of the Abyss: OBERON.
- Bottomless Pit: His Hollow Worm is the concept of falling endlessly into the pit Cernunnos was thrown in, the true nature of the last Calamity, the Insect of the Abyss. In practice it acts like a mobile black hole that sucks up everything into it, and it can be seen sucking up the shattered remnants of Faerie Britain on the chapter map once it's summoned; the battle against Oberon Vortigern takes place inside the Worm itself as Chaldea falls inside it even as they're still fighting. Its power is such that it can suck up the entire planet, this being the collapse predicted by Sion which Chaldea is trying to prevent. Holmes analyzes being inside the Hollow Worm is in some ways even worse than inside a real black hole, since there is literally no way to escape from the inside - Chaldea only escapes because Melusine was able to force open a path from the outside.
- Brainwashed: Was inadvertently brainwashed into thinking he was Oberon. It gets undone when Morgan orders Barghest to kill him and burn down his forest in Wales, killing all the fairies who believed he was Oberon.
- Brainwash Residue: Even after the brainwashing was undone, Vortigern still wishes to fulfill Oberon's goal of destroying Proper Human History. This is signified by how he is referred to as "Oberon-Vortigern" as if they are halves of the same being.
- Color Motif: Oberon initially presents himself with warm colors in his attacks, Noble Phantasm, and outfits, indicating a friendly nature as an ally to the party, but he switches over to black and cold blue when he becomes antagonistic.
- Combat Pragmatist: Will kill his enemies in their sleep for an easy victory.
- Confusion Fu: His class changes each time he's used as story support in Lostbelt 6, including Caster, Archer, and Rider. His class reveal settles this by revealing that he's actually none of them and is a completely new class, Pretender.
- Con Man: Oberon has a reputation in Fairy Britain for borrowing money and not returning it. He brought millions in counterfeit money to an auction.
- Consummate Liar: Combined with Compulsive Liar. Lies are a part of Oberon's very being, something he can't escape; his words and deeds have been labelled in human history as lies regardless of what he does, and as a result a curse has been engraved into his nature since birth that basically states "nothing about you is true, and nothing you say is true", represented by his A Midsummer Night's Dream skill. His identity as Oberon is all a lie created by fairies. His name of Vortigern while closer to the truth is misleading. He either tells quick lies for short purpose or orchestrates events to serve a greater purpose. Even as a playable Servant, his appearance as Oberon seems to be him pretending to be Oberon before his real identity is revealed. It is hard to tell where his lies end and the truth actually begins, with you requiring to doubt him several times across the entire chapter to unlock a special scene where he has to tell you the truth for calling him out as a liar.
- Death-or-Glory Attack: Casting The End Of The Dream EX on any Servant (optimally a Buster Servant) is this in a nutshell, since they're trading the chance for a huge damage bonus on their NP for certain death at the hands of any enemy that's left.
- Did You Just Flip Off Cthulhu?: Oberon straight up calls Koyanskaya disgusting during their first meeting.
- Difficult, but Awesome: Using Oberon as a support Servant has you asking "Do I want to sacrifice damage for additional NP charge?". Besides the difficulty presented by End of the Dream, Morning Lark gives a delayed debuff that drains 20% of the target's NP gauge at the end of the turn, meaning that he has a hard time settling for Quick and Arts looping due to him hindering their NP gauges. However, he is the only Servant in the game who can give out 70% NP charge when needed, unlocking more options for Servants who are just short of a full NP gauge with other supports. The application for Oberon is to be a third support to cap out any needed NP gauge needs or act as a second attacker so that the main attacker doesn't need to use their Noble Phantasm as many times. Not to mention that his Noble Phantasm applies invincibility to all of the enemies so if for some reason Oberon is unable to finish those enemies off with his NP and you lack a Servant/CE that can Pierce Invincibility within Oberon's party, you have to wait another turn to finish them off.
- Draconic Abomination: A major trait shared by Vortigern of Human History Britain and Vortigern of Faerie Britain is their draconic trait. The former is the personification of the white dragon of Britain, and transforms into a dragon himself; while the latter is considered a dragon due to his connection with the Hollow Worm. However, the Worm is best described as being an abstract monstrosity the size of Faerie Britain (1,440 km long to be exact), resembling a gigantic maelstrom of insects and curses with giant wings that look more like roots in the vague shape of a cross between a dragon and dragonfly, being the materialization of the bottomless pit Cernunnos was trapped in that tries to suck the world into itself. It gets to the point that he is one of a handful of Servants not Weak to Enuma Elish.
- Dramatic Irony: Oberon spends much of Avalon le Fae soothing the Protagonist's trauma from pruning the other Lostbelts. Oberon is also immensely resentful of the tales of the Lostbelts being cut short by the Protagonist's pruning of them. If Oberon wasn't the literal embodiment of lies, he would smash the Protagonist's Trauma Button to hell and back and then smash it again for good measure.
- Early-Bird Cameo: First appeared in the second Cosmos in the Lostbelt opening, framed in shadow and giving a Slasher Smile.
- Energy Absorption: Another trait shared by both human history Vortigern and Faerie Britain Vortigern is their status as a light devourer. Proper history Vortigern can devour light from Excalibur-class holy swords to the point they temporarily become ordinary blades, while Artoria Avalon states her holy sword is both a source of nourishment and a poisonous hazard for Oberon Vortigern; its light can feed him, but wounds caused by the blade will impair him.
- Final Boss: He's the last antagonist and boss faced in the sixth Lostbelt, but only makes his move after Morgan and Cernunnos have been defeated, and must be stopped before he escapes outside the Lostbelt and destroys the entire world. It crosses over into Post-Final Boss territory, as while he's a world-destroying threat like Cernunnos he requires far less effort to defeat both in the narrative and in gameplay, and lasts only a single section before he's defeated.
- Foil: Both Oberon and Merlin are inhabitants of "Dream World" who share similar skills - Veil of the Night vs. Dreamlike Charisma, End of a Dream vs Hero Creation. But the thing that greatly contrasts the two is their attitude in regards to stories. Merlin's Lack of Empathy means he has no real attachment to stories and has no problem carrying out tasks to get the conclusion he wants to see. Oberon on the other hand finds all stories valuable, which includes the stories told in the Lostbelts, and detests Proper Human History for culling away the unfinished stories that the Lostbelts told. How they grant support also contrasts with each other, as while they're both highly versatile and functional in different teams, Merlin's support is slow but constant, while Oberon offers quick, high damage on Noble Phantasms but high drawbacks if the battle persists after you use those skills. Their Noble Phantasms are also similar in appearance, granting the image of idyllic scenery, but Garden of Avalon offers constant Health, NP and Star Regen, while Wry Rhyme Goodfellow deals high damage, places your foes asleep and makes them invincible for a turn. Finally, their appearances both place them as pretty boys, but Merlin is predominantly white while Oberon's true form, Vortigern, is predominantly black.
- Forced Sleep: His Noble Phantasm inflicts Sleep upon his enemies. To prevent them from waking up early, an Invincibility buff is applied to them (explained away by flavor text as putting them in a dream realm), though servants with Invincibility Pierce can damage them at the cost of waking them up. In adfition, his third skill induces an unremovable sleep debuff on an ally after giving them a very potent damage buff.
- Early into Lostbelt No. 6, Oberon expresses concern that the amnesiac Mash may have supernaturally become the Child of Prophecy identity that the fairies were putting on her. As it turns out, something similar happened to him as he really did think he was Oberon after the Welsh fairies gave him that name.
- In the beginning of part 2 of Lostbelt No. 6, Goredolf mentions how Morgan le Fay of Proper Human History was actually the second fairy embodiment of Britain after her uncle Vortigern. Muryan commented earlier that Oberon does not resemble any fairy in the Lostbelt, hinting by fairy standards that he's extremely unusual.
- When he narrates how he first manifested in the Lostbelt, he's seen with the dragonfly wings of his true form rather than the butterfly wings his Oberon identity has.
- After the Welsh forest is burnt down, he takes off by himself after one of the surviving enemy commanders. The commander is attacked by a dark corruptive substance that he finds familiarity with by citing the Mors Wars and that it's something Morgan would be familiar with before being consumed by it. As it turns out, Vortigern was summoned once before into the Lostbelt as the first Great Calamity, the King of the Mors that attempted to destroy Faerie Britain with an army of such monsters in the same-named wars.
- Chaldea's first visit to Londinium reveals a mural of Cernunnos and the six fairies called Insect of the Abyss, with what appears to be a dragon skull beneath the pit Cernunnos is standing in. It's initially mistaken as a depiction of Faerie Britain's creation with the dragon skull representing Albion's corpse being used to build Britain's northern half, until Da Vinci reveals it actually depicts a possible future, namely a Calamity that could escape from the Lostbelt and lead to the collapse they're trying to prevent. This mural actually refers to Vortigern, who is associated with dragons, and the skull is the Hollow Worm that is the weaponized concept of falling into the Great Pit Cernunnos was sleeping in.
- The entire story chapter has multiple unskippable dialogue options, most if not all of them having the option to either trust Oberon or cast doubt on him, making it clear that there is something up with him. In fact, picking enough of the "doubt Oberon" options will unlock special red dialogue options when Oberon-Vortigern reveals himself that get automatically selected, leading to a optional scene with you and Oberon a little bit later.
- Gaia's Vengeance: As a Calamity, Vortigern is one incarnation of Faerie Britain's hatred towards its inhabitants, born as a method for the island to commit suicide by having him destroy it. He has a special status compared to the other Calamities, as Britain goes as far as to incarnate him twice to fulfil this purpose.
- Giant Flyer: Despite being absolutely colossal with its 1,440 km body length and equally enormous wingspan, the Hollow Worm can actually fly unhindered by gravity.
- Glass Cannon: In gameplay Oberon Vortigern has no kind of defense buffs whatsoever, but his absurd NP Charge and potent damage boost makes him very viable for huge damage.
- Graceful Loser: Takes his loss to Chaldea much better than his PHH counterpart did to Altria, and honestly wishes them good fortune in their journey ahead.
- Hates Everyone Equally: Vortigern says he dislikes "everything." Like everything else about him, it's hard to tell if he's lying or not.
- Heinz Hybrid: Goredolf states Proper Human History Vortigern is a Fae embodiment of Britain's will (specifically to preserve its Mysteries and destroy its humans); he is also human in flesh and blood who then transforms into a dragon at the end of his life. This Vortigern is also an incarnation of Britain's will (specifically to destroy the Faeries and their sins), a dragon and a Fae at once; but it's unclear if he has been a Fae since the moment he is summoned into Faerie Britain as the first Calamity King of the Mors, or if he only becomes one after he is brainwashed and corrupted into Oberon.
- Hell Is That Noise: Occasionally when using his Noble Phantasm as Vortigern, the Hollow Worm may bellow out an incredibly frightening roar as it swallows the enemies whole.
- Hoist by His Own Petard: There's nothing stopping a player from casting The End Of The Dream EX on Oberon himself (in fact, he outright benefits from both of its effects), turning him into a walking target.
- Humans Are the Real Monsters: Oberon believes that humans, specifically of Proper Human History, have no place to judge the stories of the Lostbelts and prune them from existence to save their own world, and he and Vortigern are unified to such a degree that when Oberon's will decides to push Vortigern towards destroying Proper Human History after accomplishing his original goal of destroying the Lostbelt, he doesn't need much convincing to follow through.
- Irony: In Proper Human History Vortigern was the embodiment of Britain's will who wanted a world dominated by Mystery and fought to keep the Age of Man from happening. In the Lostbelt, Oberon-Vortigern seeks to destroy Faerie Britain, which is exactly the kind of world the other Vortigern wanted.
- It's Personal: Zigzagged regarding his relationship with Morgan. Ever since his first incarnation as King of the Mors, Vortigern did everything he could to kill her and undo everything she had ever done by destroying Faerie Britain, and there is no denying he has a degree of hatred toward her, which is mutual on Morgan's part. However, upon his Third Ascension, he claims the reason he didn't actively contribute to and simply watched Morgan's death in the Lostbelt is because he acknowledges he was only born as a response to Morgan's actions in preserving Faerie Britain, and he doesn't hate "the picture book she drew" - as in, he doesn't hate the story she has created.
- Jekyll & Hyde: As Oberon, he has an almost infectious amount of cheeriness, if bordering on sarcasm at times. As Vortigern, he becomes utterly pessimistic and blunt, if still affable. It's to the point where he has different My Room lines depending on if he's presenting himself as Oberon or Vortigern; cheery comparisons made as Oberon will do a total 180 as Vortigern and vice-versa, and his opinions on Servants will likewise fluctuate, even having multiple lines for the same Servant.
- Kick the Dog: He arrives on Storm Border on Blanca, who had absorbed enough curses from Cernunnos that she dies right after landing. All that Oberon does is give her a half-hearted thank you and then just kicks her off the Storm Border until you read Oberons Bond Craft Essences text, A Pavane for a Dead Princess. Turns out Blanca, the princess of the Welsh forest, fell in love with Oberon the moment she saw him. She was aware of his hatred/disgust of everything and everyone in the Faerie Britain, but when she understood what he truly hated the most (left ambiguous, but possibly himself whos implied to not have despised the Welsh fairies completely, despite hating them and having to destroy them in the end like everything else), she vowed to flap her wings for him until the last of her days wishing it can bring warmth to his cold limbs someday. The text implies that Oberon was aware of Blancas feelings but kept it to himself to the end, which makes sense if you think about his trait as a Pretender; everything he says gets twisted into a lie, so even her love will become tainted if he acknowledges it in any way. Oberon saying Oh, youre dead? Well, I dont really care anyway likely means the opposite, and him flicking her corpse off Storm Border before starting the battle is probably coming from his intention to not drag her down to the Abyss along with Chaldea and himself.
- Kick the Son of a Bitch: All his villainous plans aside, when he boasts that he achieved his goal of destroying Faerie Britain, seeing that it's a big World Of Jerkasses who had squished every one of its sympathetic elements into the ground because of not adhering to their usual awful mentality, it is likely a boast most players wouldn't feel too bad about.
- Know When to Fold 'Em: Once in his 3rd Ascension Vortigern has no issue mocking most of the Servants from Faerie Britain to their faces... except Melusine/Albion. Vortigern even disperses himself to avoid meeting and being detected by her, though he still insults her when she is out of earshot. Likely justified, since Melusine has advantage against him in many ways - see Logical Weakness below.
- Kung-Fu Wizard: His real fighting style is much more snappy and aggressive than the more whimsical one he used as Oberon.
- Living Lie Detector: He has Fairy Eyes which can detect lies.
- Logical Weakness: The Hollow Worm is a titanic mass of curses which function like a mobile Bottomless Pit in practice, capable of harmlessly sucking in most forms of attacks and eventually the entire planet given enough time. However, the Hollow Worm requires time to annihilate all the things it devours; sufficiently resilient objects will endure the insides of the Hollow Worm as they fall infinitely until they melt away. While normally there is no way for anything inside the Hollow Worm to escape, individuals with Flight abilities and sufficient agility can avoid getting sucked in the first place, and powerful enough attacks can inflict temporary damage to the Worms body and create an opening within the bottomless pit to the outside - this is how Melusine opens up a path for Chaldea to escape out of the Hollow Worm at the Lostbelts finale.
- Mistaken Identity: Was mistaken for Oberon by the Welsh fairies, which made him think he was Oberon.
- Mutually Exclusive Powerups: He has a passive skill called Anti-Human Order D that increases party debuff chances on non-Foreigners, and makes Merlin's buffs get a 20% chance of not working. Its name is only revealed if the player has cleared Avalon le Fae.
- Naked on Arrival: In his 2nd manifestation in the Lostbelt, he didn't have any clothes or armaments as he was improperly summoned. He's initially presented in flashbacks for when this happened looking relatively normal, sleeping in warm sunlight as the insect fairies marvel at him. Then The Reveal hits and the same flashback is revisited, except this time, his body is very sickly with his skin deathly pale and his eyes ominously staring into nothing. The insects are crawling all over him and the background has no trace of sunlight, being a similar shade of green as his eyes.
- Non-Action Guy: Oberon claims he can't fight. He is pretty handy with a sword though. However true that might be of the Heroic Spirit Oberon specifically, however, it's definitely not true of Vortigern.
- Non-Standard Character Design: To stress his otherworldly nature, he has a very distinct look that sets him apart from the already diverse cast of Servants courtesy of Chica Umino. Nasu stated on his blog that he specifically asked Umino to stick with her usual style instead of trying to fit Grand Order's style. He becomes even more otherworldly in a sinister manner with his true form, still drawn in the same style as before. This is especially notable as Umino has entomophobia (fear of bugs), yet did her best to study insect anatomy to give the best result possible.
- No-Sell: A Midsummer Night's Dream EX gives him immunity to Mental Debuffs and Curse.
- Older Than They Think: Discussed. As Tristan explains early into the Lostbelt, while A Midsummer Night's Dream is Oberon's most famous potrayal in modern days of Proper Human History (and in real life), he has existed in folklore and literature for centuries before then. Caesar's profile also mentions a myth that he slept with a fairy, though it didn't mention if that same myth resulted in him fathering Oberon with her (one of Oberon's older origin stories). As Shakespeare and his works don't exist in the Lostbelt, the identity of Oberon forced upon Vortigern by the Welsh faeries should have been this "Oberon, the Ancient Faerie". However, Vortigern is instead brainwashed into "Oberon, the Faerie King" which is indeed born from A Midsummer Night's Dream, because Morgan's actions throughout the Lostbelt's history had created several links with PPH and allowed this Oberon identity to manifest.
- Omnicidal Maniac: A step up actually from Proper Human Hisyory Vortigern in the Garden of Avalon novel, who sought simply to wipe out mankind to ensure a world dominated by Mystery; in the time Vortigern spent undermining the Lostbelt, seeking to destroy it so he could escape, he decided to elevate his goal to simply annihilating ALL of Proper Human History, which includes the world. Uniquely, he did not originally want to destroy Proper Human History, but after he was brainwashed into becoming Oberon, he ended up wishing that (even after the brainwashing got undone).
- Omniscient Morality License: Similar to Shakespeare, Oberon will do things because he thinks it fits the narrative. For example, he waited before finding the Protagonist and Altria Caster because he thought it would increase their Relationship Values. Unlike Shakespeare he's not doing it because it amuses him but because that's how he thinks stories work. Notably, this is mildly implied to be the reason why Oberon didnt backstab Chaldea when they were fighting against Cernunnos, even though had he decided to go against them at that point Chaldea would likely have lost and Cernunnos would have destroyed the planet (and Proper Human History) for him.
- One-Winged Angel: Another trait shared by both Proper Human History and Lostbelt versions of Vortigern is his habit to grab an external source of power just in time and then transform into a dark Draconic Abomination. Proper Human History Vortigern as a dragon is powerful enough to drain the light of Excalibur and Galatine (Anti-Fortress and Anti-Army Noble Phantasms, respectively) which temporarily reduces them into ordinary swords, then casually releases magical energy vastly above that magnitude to fight Altria and her Round Table Knights. On the other hand, Oberon-Vortigern as Insect of the Abyss proves capable of fighting Chaldea and Altria Avalon after her ascension as the materialized concept of Holy Sword user, which is on par with if not superior to Grand Servants and Divine Spirits.
- Perception Filter: Its later revealed throughout your journey through Faerie Britain, Merlin is unaware that Oberon even exists since he cannot even see him, making him think that you've been talking to yourself the entire time. Oberon dislikes Merlin so much, he allocated all of his camouflage abilities towards keeping him from being seen by his Clairvoyance. This ability to conceal himself from observers, even high level Clairvoyance on Merlins level, as well as how Chaldeas sensors pick up his Hollow Worm form as a hole in reality, gives him an uncanny similarity with the Priestess of the Foreign God.
- Person of Mass Destruction: Twofold. When first summoned into the Lostbelt as King of the Mors, Vortigern was able to corrupt an untold amount of Faeries into Mors, enough to be considered the first of Six Calamities, and fought Morgans forces in a war with them. Then once Cernunnos is defeated and he realizes his nature as Insect of the Abyss, he takes this up a couple notches by being able to suck in everything (up to and including the entire planet) into the pit Cernunnos was dumped in. Oberon Vortigern himself has powers comparable to Grand Servants, enough to face Chaldea, Mash, and Altria Avalon in single combat.
- Pest Controller: In his Oberon form, he can summon butterflies when using his skills or to bombard the enemy with their glistening dust. Once his true form is revealed, his arsenal comes to include massive pillbugs that he can kick into the enemy and ravenous dragonflies. He can't order them to be quiet or leave him alone though, and resorts to using bug spray when he wants some peace and quiet.
- Pet the Dog:
- He's the one who teaches Altria Caster magic and not Merlin (he merely introduced himself as Merlin, and because it was through telepathy, Altria didn't know his face) because one day Altria mentions she wishes she could make fire as the stable she's staying in is very cold. Despite being actually incapable of using magic, he goes through the pain of learning it in order to teach Altria how to do it, and this goes on for about a year; Altria will mention what she wants to learn, and Oberon-Vortigern will learn it for a few days before teaching it back to her. This is why the majority of Altria's magic is rather unique and oddly specific.
- Oberon admits that he wouldn't have answered his Master's summons if he didn't like them. Even in his true persona Vortigern, who hates pretty much everything in existence, also says that his Master is among the few things he actually likes. He tells them to exercise caution when handling the poisoned letter he made for the purpose of killing Shakespeare.
- Power at a Price: His third skill, The End Of The Dream EX, is easily the biggest example in the game so far. The Power granted to the selected ally is a 50% increase to Buster effectiveness, and amplifies any NP damage buffs the ally has by up to 100%, (this includes NP damage buffs from Craft Essences like the Black Grail) which can result in bigger damage potential. The Price on the other hand is a framed Demerit clock debuff (meaning it cannot be removed at all though you can delay the effects if the Guts buff gets triggered the end of the turn), and on the next turn, the ally's buffs are removed (which outright ignores buff removal resistance), they take a Taunt debuff, they cannot be switched out or sacrificed, and as the final kicker, they suffer a PERMANENT SLEEP DEBUFF which will never, ever go away by any means, even if the ally is attacked. In short, it supercharges the Servant for one turn, then turns them into complete and utter dead weight for the rest of the battle. This makes the skill only useful in the final wave of quests (where the demerit won't matter), as a Death-or-Glory Attack, or for someone like Arash and Habetrot who can kill themselves. Arash in particular has unholy synergy thanks to his NP being an already hard-hitting AOE Buster, making him the perfect recipient.
- Power Limiter: It's Cernunnos himself. As long as Cernunnos exists Vortigern cannot summon his Hollow Worm, so he goes to the trouble of manipulating both sides so Morgan and Cernunnos can be defeated. Once they're out of the picture, the predicted collapse finally begins after being kept in mystery the whole chapter.
- The Power of Hate: Outright exclaims as he reveals himself that he is defined by his immense hate towards mankind, so much that he spells out that he is capable of being classified as a "Threat To Humanity", a thing only a handful of enemies (usually Foreigners and those related to them) have been classified as, almost in spite of the fact he cannot be a Beast-class enemy due to the fact that Vortigern is so immensely hateful that love is normally lost on him completely. That said, however, due to his Brainwashing as Oberon he is able to recognize and yearn enough for the idea of Titania, an entirely fictional character that Shakespeare created to be paired with the much more ancient idea of Oberon, that it is able to give Vortigern the faintest idea of love and fight as hard to want to meet Titania as much as he wants to destroy everything.
- Pragmatic Hero: Even as Oberon, he still had his rough spots. Most notably, he hides info about the full prophecy Altria Caster and Chaldea are trying to fulfil like how Norwich was meant to be destroyed by the Calamity, and makes under-the-table deals with Koyanskaya to advance the fight against Morgan.
- Rage Against the Author: Oberon definitely has a problem or two with Shakespeare. His My Room line for him has him writing a heartfelt letter to "his author", only to tell you to deliver the letter to "that bastard" and warning you that the wax seal and the ink he used is filled with poison.
- Readings Are Off the Scale: Lie Like Vortigern is an Anti-World Noble Phantasm with an EX rank, like Fujino's Vijñāpti-mātratā and Kama/Mara's Mara Avaruddha. However, the Range and Maximum Targets are both listed as being Unlimited.
- Reluctant Monster: Downplayed. While Vortigern is filled to the brim with disgust and hate toward the inhabitants of Faerie Britain, some of his words imply he has a degree of unhappiness with his role as its destroyer, without any choice on his part. His Interlude shows he is much more relaxed and content without being shackled to the role forced upon him by Faerie Britain, and his line toward Morgan after his Third Ascension suggests he might not have attempted to destroy Faerie Britain if he had any choice in the matter. Koyanskaya also states that Vortigern is filled with self-loathing unlike herself who takes pride in her evil deeds.
- Secret A.I. Moves:
- As the Final Boss of Avalon le Fae, he can use a skill that inflicts Sleep on various party members alongside a timed debuff. For obvious reasons, this skill is not available to the playable Oberon.
- His Bonus Boss variant in his interlude has him use End of a Dream EX without having it inflict a timed debuff where it inflicts the Eternal Sleep debuff on anyone he uses it on.
- Secretly Selfish: While Oberon comes off as being the "good personality" of the two, he's the one who wants to destroy the Proper Human History. As a character who originated from a fictional play, he is spiteful towards humanity and how the world approves of them by culling away the stories that Lostbelts tell. All that Vortigern wants to do is destroy the Faerie Britain, but Brainwash Residue causes him to carry out Oberon's wish to destroy the Proper Human History.
- Shaping Your Attacks: Several of his projectiles decay into a suspiciously dark-looking mud-like substance after they connect with the target. It's foreshadowing how he was the King of the Mors by having a more refined version of their sludge attacks.
- Shown Their Work: On the first glance, having Vortigern of Arthurian Legend pretending to be the Shakespeare-popularized Oberon might seem to be the most random combination. However, there exists a play named Vortigern, an Historical Play that was believed to have been a genuine Shakespeare play but was shortly after proven to be a Shakespeare hoax and mocked upon the first performance, meaning that "Vortigern" has some history to mimicking Shakespeare's work.
- Sigil Spam: The inside of his cloak is covered with the Thistle Royal Badge of Scotland.
- Sinister Scythe: He can conjure one, seemingly made out of an insect's leg, in his boss fight.
- Situational Damage Attack: His Noble Phantasm does additional damage to Lawful servants.
- Sleep-Mode Size: He can shrink down to the size of a moth, represented in his art as a chibi version. He calls this his "Robin Goodfellow" form. His Extra Attack animation shows that he can still fight while in this form.
- Squishy Wizard: His official statistic has both his Strength and Endurance at Rank D. That being said, every other stat is highly-ranked to compensate, with Lie Like Vortigern being an Rank EX Anti-World Noble Phantasm with Unlimited Targets and Range.
- Star-Crossed Lovers: Even though he knows that she's a fictional character and admits it's a pipe dream, he wants to meet Titania, saying that she is the only person who could love the eccentric King Oberon. Even after remembering his true nature, he admits that he still clings to finding his ideal in Titania someday.
- Support Party Member: Oberon's skillset is focused on supporting himself, or his allies, especially when it comes to Buster-oriented teams. His first skill Curtain of Night EX increases the party's NP gauge by 20% and gives a 20 to 30% damage increase for 3 turns. His second skill Morning Lark EX increases a single party member's NP gauge by up to 50% and drops 10 to 20 crit stars in exchange for reducing the gauge by 20% a turn later. His third skill, The End Of The Dream EX, confers a unique and very powerful benefit to a party member, but see Power at a Price above for more details about it. Unlike fellow Support servants like Merlin though, he has a damaging AoE NP that does huge damage (even more vs Lawful Servants) and gives them the Sleep status in exchange for also giving them Invincibility for one turn.
- Suspiciously Similar Substitute: If Cernunnos is a Tiamat analogue, then Oberon-Vortigern is Surtr. They are Omnicidal Maniacs initially overshadowed by the local Lostbelt Kings, hiding under false identities, manipulating both sides in order to unleash their true power, and capable of breaking free of their Lostbelts to threaten the entire planet.
- Tactical RockPaperScissors: His true class plays like a reverse Alter Ego; he does extra damage to the Knight classes while doing half-damage to the Cavalry classes (except for the Mutual Disadvantage Berserker class). Additionally, he has the offensive and defensive class advantage to Alter Ego servants while having the offensive and defensive class disadvantage to Foreigner servants.
- Taking the Bullet: He does this in the climax of Lostbelt No. 6 Part 2 for the heroes when Morgan's clone attacks them after they've let their guards down. He pretends it killed him so he can make his moves in the background of Part 3.
- Teeth-Clenched Teamwork: If summoned after completing Avalon le Fae, which means defeating him as its Final Boss, his summon quote will change to reflect the absurdity of the situation — that he's now being forced to fight for the very Proper Human History he just tried to destroy. He makes clear from the get-go that he had no intention of "redeeming" himself like other summoned villains and is not pleased with this turn of events....What's going on? Why is this happening...? Oh, I see. So even lies are permitted until the Human Order is restored? Hm... very well, I give up. After all, that's the kind of human you are. My name is Oberon. Now that I've been summoned, I will lend you my power. It truly is an unpleasant feeling though, don't you agree?
- Theme Music Power-Up: His Noble Phantasm theme is a short snippet of his boss theme.
- Two Aliases, One Character: This man first materialized into Faerie Britain as Vortigern, started the first Great Calamity as the King of the Mors, was brainwashed by the fairies in the Welsh forest to become Oberon, pretended to be "Merlin" in order to teach Altria Caster magic and finally became the last of the Six Calamities as the Insect of the Abyss. So in total he has five different aliases as just one character. He's actually pretty proud of having a ton of names and titles to go by.
- Walking Spoiler: The third part of Avalon le Fae reveals many things regarding his true identity, the least of which includes the fact that he's actually in a completely new Servant Class for the game and that he's actually a completely different character under the belief he is Oberon. It's to the point where players who haven't completed Avalon Le Fae and his interlude but were able to summon him can not view his last two ascension arts.
- Wings Do Nothing: Oberon's wings are essentially nothing more than decorations as he is unable to fly with them. He playfully laments this after being defeated, falling for eternity in his own Hollow Worm.
- You Don't Look Like You: Understandable in this case, as "Vortigern" is the name for an avatar of Britain's will, and the forms that agent takes in Proper Human History and Faerie Britain are very different. PHH Vortigern, from how he's described in the Garden of Avalon novel, comes off as an enormous Tin Tyrant akin to Sauron (which partially forms the basis of Saber Altria Alter) who eventually transforms into a literal Draconic Abomination against Altria. When he is finally defeated, he withers into the form of an old, human man. Faerie Britain's Vortigern is a very different entity with a very different approach, secretly working to engineer Britain's destruction through a Mêlée à Trois.
- You Remind Me of X: His Oberon personality is, as Altria Caster puts it, "Merlin-esque." Becomes a major case of Irony since Vortigern himself hates Merlin with a burning passion, but then becomes foreshadowing with The Reveal that he was the one who taught Altria Caster, not Merlin, and just used Merlin's name.