Arthur is the main protagonist of Capcom's Ghosts 'n Goblins franchise.
Arthur is a knight who fights against demons, zombies, and other creatures to rescue the Princess of Hus (names varying from Prin Prin to Guinevere) from Astaroth and other demonic villains. While his armor looks sturdy it is infamous for only being able to take a single hit from enemies, leaving Arthur comically running around in his boxer shorts. One more hit will kill Arthur instantly, leaving him as nothing but a skeleton. Arthur also uses several weapons on his journey, most famously the lance, which is used in his Mii Costume.
Arthur's story initially begins in Ghosts 'n Goblins when he and the Princess are meeting within the vicinity of the nearby castle, having his wounds treated from when his platoon of knights and wizards having an encounter against the army of the Demon Realm. Suddenly, the sky goes dark as the evil presence of the Demon Realm creeps over the kingdom, turning what was to be a sunny day into an endless night. A demon known as Satan swoops in and captures the Princess and vanishes from whence he came, forcing Arthur to don his suit of armor and venture forth to rescue the Princess, starting in the Graveyard near the village. Through his adventure, Arthur faces off against a number of Cyclopes, Dragons, and Satan himself. Arthur makes his way into the Demon Realm's castle where he fights the leader of the Demons, Astaroth. Although he seemingly defeats the Demonlord, the room was an illusion and a devious trap installed by Astaroth, sending Arthur all the way back to the Graveyard, the venture to him following the Princess' abduction being nothing more than a dream. Arthur makes it to the castle once more, carrying a Cross in hand and fighting the true Astaroth. With the Demonlord defeated, Arthur and the Princess are reunited.
Returning the Princess home from the arduous journey, Arthur sets out to patrol the far reaches of the kingdom. After three years, he returns to find the kingdom under attack from a new demonic horde. Arthur barely manages to get to the Princess before she is hit with a beam of energy, sucking her soul out of her body. Arthur now sets out on his second quest, making his way to the Castle of the Evil Demons, battling more fearsome foes as well, including the Shielder, Cerberus, Gassuto, the corpse of a giant insect known as the Ohmu, and the lord of the flies Beelzebub. Upon defeating the Castle's most powerful guardians, including a revived Astaroth, Arthur is met by the archangel St. Michael, telling him that the only way to rescue the Princess' soul is to find the Psycho Cannon and bring it to the door. Arthur retraces his steps from his current adventure and meets the Valkyrie. The Goddess of Battle gives Arthur the Psycho Cannon, which allows him to face the leader of this new invastion, Lucifer. In a fierce battle, Arthur defeats Lucifer, freeing all the souls that he had consumed and restoring the Princess' soul into her body.
Time passes as life returns to normal in the kingdom. But one night, a third band of demons attacks the kingdom on what would have been a joyous occasion. Satan appears once again and carries the Princess off to his master, forcing Arthur to venture into his third quest. Once again, Arthur faces off with terrifying enemies, namely the Cockatrice, the Shell Head, the Death Crawler, the Hydra, and the Ice Warlord. Arthur makes his way into the castle of the new leader of the Demons, Samael. But before he can get into Samael's chamber, he receives a psychic link from the Princess, telling him that the one thing he needs to destroy Samael is her bracelet, now revealed to be the Goddess Bracelet. Arthur once again retraces his steps and finds the Bracelet under the protection of fairies. Returning to Samael's Castle, Arthur fights against Astaroth's second revival and his transformation into a more powerful being known as Nebiroth. After Nebiroth's defeat, Arthur faces off against Samael himself, defeating the newest general of the Demon Realm. Arthur and the Princess arrive home safely, watching the sunrise from the back of Arthur's horse.
This peace was not to last as a new Lord of Darkness had already begun orchestrating his plan to use the Princess to create a mixed-blood union between Humans and Demons, allowing the Demons to lord over the Humans, and destroy Arthur once and for all. Arthur barely arrives in time to see the Princess spirited away to the Demons' Black Palace. While fighting his way through this new gauntlet of demons, Arthur uncovers a number of Magic Rings, which open a portal within the depths of the Black Palace. Along the way, Arthur encounters the newest set of minions set against him by the Lord of Darkness, primarily the Sorcerer, Arthror, Death Curse, the Dust Manteater, Vermirous, Slugel, the Spiral Mantruder, a Black Dragon, and the Witches Union. Arthur makes his way into the Palace and faces off with his eternal nemesis Astaroth one final time, entering the portal created from the rings. It is in this dark domain that Arthur encounters the mastermind, Hades. After a long intense battle, Arthur destroys Hades and brings peace back to the Human Realm, with the Princess safe and sound.
At some point in Arthur's journeys, he encountered an elite Red Arremer demon known as Firebrand and fought against him. Red Arremers have been a constant thorn in Arthur's side in all four of his adventures, being an unpredictable sort of flying demon boasting great speed and endurance, with Firebrand being one of the most well-known among them. It is unknown to what extent the two knew each other, but Arthur had seemingly known of a legendary demon who fought in the War for the Crests and was also known as the "Red Blaze," both of which are descriptions that apply to Firebrand himself. It is implied by the Game Boy Advance release of Super Ghouls 'n Ghosts that Arthur and Firebrand fought in the Village of Decay during his second adventure into the Demon Realm, with Firebrand wearing a suit of reinforced armor and taking the rank of "Red Arremer Joker," a title belonging to the ruler of other Red Arremers. The two come to a draw with both knight and demon recognizing each other's strength.
Arthur appears in Ultimate in two major roles.
As a Mii Costume
As a spirit
Arthur also appears as an Ace-Level Grab type Primary spirit. His spirit is only obtainable when save data for Ghouls 'n Ghosts Resurrection is detected; he will be available for purchase in the shop at a later date.