Terma Lane, an Azur Lane story

There Shall be One that Rules the Ocean, 1943

1943, and the seas are calm. Yet, that calm is interrupted by a group of destroyers and submarines from the nation of Asami. Trislandia had reached out to their allies and recruited help. Now, the group searches for the Royal Battlecruiser. The group consists of 3 submarines and 3 destroyers. 

After a long search, they finally spotted a contact in the radar. It's huge, which is something that they are looking for. The group prepares and then approaches the large contact. Sure enough, the silhouette identification shows that the ship is indeed a Bastion class. They report back to their allies from Trislandia, and the Asamian submarines close in.

But one of the submarines, I-606, shows confusion.
"Do we have to fight? I can't bring myself to fight her, because she saved me from sinking last time I met her."

Her submarine sisters sigh and one of them asks
"Alright, what do you suggest?"

"I'm gonna contact her."

"That's risky!" The other sister exclaimed, she has never heard of either that much bravery or stupidity,

"I know, but I'll try anyways." I-606 said as she closes in on the battlecruiser, on silent run. She starts up her radio and talks.
"Bastion... Bastion... do you copy? This is I-606."

There was no response coming from Bastion. Not even a movement of her turrets. But deep down... Bastion knows who this is. She couldn't speak or move her own body, because a siren is in control of it.
"Wait... This is... The one that I rescued? No... No! Get out of here!"

"Oh? Thank you for telling me. Let's see how you fare watching her suffer." The siren controlling Bastion's body decided to take matters into her own hands, and possibly torment the real Bastion.

"No! YOU LEAVE HER ALONE!"
But she couldn't do anything except watch as the siren tries to locate the submarine.

The Sub doesn't know anything about Bastion's current condition, yet she still wants to contact her. She rises to periscope depth and looks at the ship and the shipgirl sitting on top of turret B. That is in fact Bastion, but her soft and motherly brown eyes are glowing blood red. Her expression is also somehwat robotic.
"Bastion please answer, i don't want to hurt you... What have they done to you..."

Then Bastion suddenly looks right at the periscope, giving it a gaze as sharp as a knife. She aims her torpedo tubes and her airplane drops sonobuoys all around. The Submarine's sisters warn I-606 about Bastion.
"Watch out! You have been spotted!"

"Bastion..." I-606 crash dives, not believing what Bastion is doing. Bastion accelerates to 40 knots and launches her torpedoes. She also aims at the Asamian destroyer group and fires HESH shells from her 12 massive 16 inch guns.

Asamian Submarines evade the torpedoes with their maneuverability and fires their own torps in retaliation. The Destroyers speed up and sails in a zig zag pattern, trying to avoid the shells and its massive blast radius. The long range engagement leaves no hits, and proven fruitless for both sides until...

The unmistakable high frequency of the Trislandian propeller noise fills the air.

"We're saved! Let's give the fun to them." I-401 says, signalling the tactical retreat of Asamian forces.

Bastion turned her main guns away from the destroyers and to the aircraft. She loaded all guns for anti aircraft duties and starts to fill the sky with bullets and explosions. The Stuka dive bombers start to dive and aim for the battlecruiser, and 5 out of the 15 diving aircraft gets knocked out of the sky. But 10 managed to release their payload in the middle of the fray, and 6 bombs hit. The two hits are on the well protected areas so minimal damage was dealt to Bastion, but the other 4 knocked out some secondaries and AA.

Then the bulk of Trislandian aircraft arrives, torpedo bombers. They line up and set the torpedoes to a depth, then launching them. Bastion has an active protection system against torpedoes, so some torpedoes are countered. yet, 3 managed to go through and nail Bastion right in the hull. "Ack!... Torpedoes..."

After the hit, the returning aircraft reports to both Neumann and KW about Bastion's condition. The two sails to Bastion and summons their riggings. All that while Bastion struggles to keep upright from the torpedo hits.

"So it was you who dare touch my brother." The fierce Neumann says to Bastion, full of vengeance.

"I do what is necessary." Bastion's cold expression just as Wiemann explained. It's true.

Enraged by that answer, Neumann fires all 15 of her main guns at Bastion. The shells missed their mark except two, one hit the armour belt at an angle and one struck the propulsion, limiting Bastion's speed to 20 knots instead of 40. 

They exchanged heavy fire at each other, while also conversing with each other.

"i'm going to make you pay for sinking my brother!"

"Your bother? He was a mere stepping stone for the war effort."

"5 years the fuhrer planned all of this. 5 years! I wouldn't allow all of that to be desecrated just because one ship that has ego as big as the Atlantic itself."

"Well his plans are apparently flawed."

Neumann can't stand talking to Bastion again so she aimed the next shot a bit to the rear. The shell ripped right through the rear radar tower. The accuracy is decreased for Bastion, who is currently moderately damaged by the torpedoes, bombs and cannon fire. But Neumann's escort ship, the cruiser J-013 Kleiner Wiemann, is preparing something that is rather new. The weapon is about to be tested against Bastion for the first time.

"Too bad Bastion, we are the superior one, with the Traumfänger, we start over from "zero", and entrust the world to the future generations. Fire the rocket!" Neumann orders to KW. The V-1E, the closest thing to a modern guided missile for the time. Active Radar guidance, with more that a thousand kilograms worth of Trialen as a warhead. It flies at a blistering pace towards Bastion, and hit her superstructure. Now, it is no more than a pile of burning scrap metal. Of course, Bastion is knocked out of action.

Neumann walks on water, approaching the stricken, dying Bastion. Neumann aims all her guns, and by all I did mean all. Main caliber, secondaries, and even anti aircraft guns. All aimed at Bastion's waterline. "Wake up Bastion, this is not the real you, its about time you also realized we are here to achieve peace as well."

"What are you waiting for? End me." The siren controlled Royal Navy battlecruiser utters her last words

"For the Fuhrer...., for the Traumfänger...., for my Brother...., succumb to your despair...." Neumann said before firing all her guns at Bastion. The main battery shells penetrated through the armor easily and reached all the way to the ammunition rooms. Both the front and rear ammunition storage rooms went up in flames, resulting in a massive explosion that can be seen from dozens of kilometers.

Of course, Neumann is also very saddened by the fact that she had to sink the ship that rescued her brother for the first time, and showed kindness and mercy throughout her life. She kneels down on the sea, tears flowing down. But that ship was also the one that sunk her brother. Neumann refused I-606's request to rescue Bastion's body from the sinking ship.