Light of the Martyrium French UR Event EX Stage Clear Guide [Azur Lane]

This video serves as a comprehensive guide about everything that you need to know about the EX Stage of Azur Lane's new event, Light of the Martyrium, which introduced a variety of new French ships, including the new UR ship Alsace. In the video you're going to learn about the main weaknesses and strong sides of the boss, about the armour type that it has and the most preferable choice of equipment to fight against it and many more. We will also discuss the attack pattern of the boss and some special mechanics of the gamemode that can make it even easier. After watching this video, you should be able to easily beat the Light of the Martyrium's EX stage without any issues!
Now let us quickly talk about my fleet composition and the possible substitutions for each of the ships, starting with the backline. I decided to go for Shinano and Hakuryuu, as they are the only ships in the game that are capable of dealing such a whopping amount of damage to the target with heavy armour type, and there is simply no direct replacement for them. However, any other ship that can carry two torpedo bombers or dive bombers at the same time should work more or less fine: Chkalov, Theseus, Implacable, August von Parseval, Enterprise, Saratoga and so on.
As for Ark Royal, she was chosen due to one of her skills having a very small chance of doubling her damage output, making it so that one of her airstrikes hits as hard as two should have. Generally she would perform a lot worse than other carriers that were mentioned, but, if your intention is to oneshot the boss in one airstrike, you can restart the battle over and over again until her skill becomes active. I got lucky and got it on the first try, though. As for Ark Royal's slowing capabilities, they are irrelevant in this fight thanks to the boss standing in one place for most of the battle. If you still want to slow it down for some reason, Implacable or Formidable would still be better.
Laffey II serves as the main tank of the fleet, and, despite her being merely a destroyer, her survivability rate is actually the highest one in the game. If you do not have her or did not level her up properly yet, the possible substitutions are every heavy or large cruiser with high defensive capabilities: Azuma, Anchorage, Kronshtadt, Brest, Aegir and so on.
Helena is the primary source of damage increasement for the whole fleet and she can hardly be replaced by some other ship. However, her META version or Sirius can get the job done, even though their effectiveness tend to be a lot lower, as everything just pales in comparison to how strong Helena is.
Kazagumo was used to ensure that the carriers will deal enough damage to oneshot the boss, as she increases the damage output by 15% as long as she stays afloat. Every other destroyer with the Air Raid Assistance will substitute her easily: Ariake, Ardent, Yuugure, Stephen Potter.
Timestamps:
00:00 The Basic Information About EX Mode.
00:26 More About The Boss.
01:01 The Attacks Pattern.
02:36 A Successful Attempt Showcase.
03:26 An Equipment Showcase.
03:48 An Outro.
The music, used in the video, in a chronological order:
Blue Archive OST 01 -- Constant Moderato -- From the beginning to 03-48.
Azur Lane OST -- Daily Life -- From 03-48 to 04-00.
Being lazy with the music once again :D
The emulator, that was used to record the video: MuMu Player.