Queen Britannia

The Queen Britannia (クイーンブリタニア号) was a luxury cruise ship and floating fortress, formerly used by the British Royal Family.

Etymology
is a word with various meanings: it is the ancient name of the island of Great Britain, the name of the Roman province that covered the island south what is now Scotland, and the name of the female personification of Britain. And just like in this case, it is a name that has been given to   in real life, including a  of Queen Elizabeth II, possibly the inspiration for the Queen Britannia.

Appearance
The Queen Britannia was a grey ship about 200 meters long and 3 stories high (about 9 meters from waterline to the deck), looking like a combination of a luxury cruise ship and a warship. Much of the interior was described as being more like that of a palace or museum than a ship, with many antiques, works of art and high-class décor. The decagonal heliport which acted as the central temple was located at the aft of the vessel.

Principles
As it was meant to carry the United Kingdom's representatives, the Queen Britannia was built to be sturdy in order to protect its passengers. Being from a magical kingdom, numerous magical symbols were incorporated into the ship's fundamental design, such that it would not be easily sunk by any damage or attack. The Queen Britannia was effectively a royal castle in the form of a ship, though more of a fortress than a palace.

Having to fulfill other functions of a royal residence, the interior of the ship was quite luxurious, including a gallery filled with famous gold-framed paintings, an opera house with three stories worth of audience seating, and a large dance and dining hall. The kitchen was located adjacent to the dining hall, containing industrial-scale fridges and counters, with stainless steel surfaces. These facilities were maintained and stocked after the ship's decommissioning for tourists willing to pay to enjoy royal cooking. Among the food supplies were blank containers apparently made for researching the Cake of Light.

A large cargo storeroom was located at the center of the ship, with various passageways leading to all other parts of the vessel. There was an elevator here which led to the heliport temple, which required a specific passage to be taken through the ship beforehand and the right secret handshakes (often used in magic cabals) to be used on the doorknobs in order to be accessed.

The ship had a displacement of about 150,000 tons, roughly one and a half times that of a nuclear aircraft carrier. It used a diesel engine which could manage a speed of 30 knots without damaging itself.

Heliport Temple
The core of the Queen Britannia was the ship's central temple, based in the heliport on the aft deck. Lacking the standard markings of a typical helipad (such as the large 'H' and warning lights), it was an open decagonal pad larger than a tennis court, with many grooves and patterns carved into its floor and the elevator along a boxy structure on one of the sides. The temple's ten sides symbolized the ten sephirah of the Sephiroth.

The temple had the effect of amplifying all magic and spiritual items used within it. This could be utilized by anyone within the temple, regardless of affiliation, and would allow them to perform larger ceremonies than they could normally manage. The many grooves and patterns carved into the temple's floor contained numerous symbols which could be used to support a ceremony, with the appropriate lines and intersections filling with white light when the symbols were to be used. The symbols included, among other things, 44 varieties of, sigils for angel names, at least one pair of equilateral triangles, and a full set of Enochian tablets.

In order to aid the temple's users in carrying out ceremonies, there were a number of meter-wide floating plates which could carry magical tools over from the edge, in response to vocal instructions and gestures. Equipment carried on the plates included:
 * A ceremonial sword without a blade and a metal plate with powder for a camphor flame, used for banishing rituals.
 * A few crystal balls, a glass panel and a fire-based light source, functioning together as a projector to enlarge and display an image on the floor.
 * A yoga mat, apparently used by a princess in the past.

Being the most important part of the ship, the temple was protected by a thick and powerful barrier. Once activated, the barrier would let things out but not let anything in - with access to the temple only possible through the ship itself, following the correct procedure. It also concealed the interior of the temple from external view. The barrier blocked practically nearly all outside interference and was resistant to most levels of brute force, capable of withstanding attacks from nuclear weapons and the likes of the Curtana. Rather than being a wall dividing worlds, it was said to be more of a constructed world placed in-between as a cushion, and as such one would require an attack capable of destroying a world, or Imagine Breaker, to break through it.

The temple was also capable of launching attacks to intercept enemies approaching the ship. Aside from its generic settings, it could also weaponize any magical tools connected to the altar (which would already be amplified by its effects) - according to the Knight Leader, even something like a or a  would produce a barrier that would distort luck so approaching ships and aircraft would sink. With the Honours of Scotland and the Stone of Scone, it unleashed a powerful barrage with 400,000 shots (100,000 of four different varieties) per volley.

Background
Created around its central temple, the Queen Britannia was built in order to carry the British Royal Family in comfort and safety across the seas, in order to perform large-scale rituals at 53 predetermined points throughout the territories of the British Commonwealth.

The Queen Britannia served and protected the British Royal Family for many years, and the princesses have numerous childhood memories from their time on the ship (including wrestling in the large beds, sneaking into the kitchen to swipe food, and in Carissa's case, secretly handling an expensive violin as a pretend sword). As necessary diplomatic trips came to be made by plane, the ship came to mean more as a show of force and technological might than as a vehicle.

After being decommissioned, the ship was moored in a harbour in Edinburgh as one of its major tourist attractions. As forcefully dismantling the ship might have resulted in a rebound which could have blown away half the country, it was instead intended that the mental noise from the thoughts of the many ignorant tourists would gradually neutralize the magical symbols over time, though it was estimated that the process would take over 1200 years.

Coronzon Arc
At some point prior to the events at Edinburgh Castle, Coronzon (in her guise as Archbishop Lola Stuart) had made arrangements for the Queen Britannia to be moved from its mooring in Edinburgh. As the ship was a valuable cultural asset and the Irish Sea was comparatively safer at that point than the east side of Scotland, which bordered the sea leading the European mainland and was therefore under threat from the Crowley's Hazards, the security crew likely didn't question the order. When the ship arrived at, Coronzon hijacked the ship, swiftly removing the people onboard, who didn't know how to activate the ship's defenses, within 30 seconds. Turning on the magical defenses, which soon shot down several Anaconda cruise missiles fired at it at around 10 AM, Coronzon accessed the central temple and prepared it for use together with the stolen Honours of Scotland and Stone of Scone in the Ceremony of Mo Athair.

While the Queen Britannia was passing south of the at 11 AM, heading for the optimum point for ceremony and due to arrive at noon, the British forces froze the surface of the  in order to slow it slightly and to provide a foothold for them to attack the ship. In the battle, the Scottish royal treasures were used in conjunction with the ship's temple to fire a barrage of 400,000 shots per volley against the attackers. The ship sustained minimal damage from external attacks (despite being rocked several times by Qliphah Puzzle 545's ice tornado supplemented by Accelerator), but various parts of its interior were damaged from the battles involving the intruders.

At the end of the battle, the ship was bisected from within by a beam unleashed by the entity within Kamijou Touma, which emerged after Imagine Breaker was severed. It subsequently sank in the half hour following noon. As the ship had many antiques and works of art onboard, it was expected that professional divers would soon search the wreck on the sea floor.

Trivia

 * Being a royal British ship, the Queen Britannia should have its name preceded by the ship prefix HMS, the abbreviation of His/Her Majesty's Ship.