A few minutes before, Leia's POV:
Leia was surprised, the awesome Darth Vader did not intimidate her at all. He pointed his index finger towards her, the same way her father Bail Organa did, when she really got him railed up. Back then she would stick her tongue out at Bail and he would take her in his arms and squeeze her. During the initial encounter with Darth Vader on the Death Star, she was really tempted to stick her tongue out at him, the very same way, but that would have been too childish, not really suitable for a Senator. In fact, when she was brought before Grand Moff Tarkin, it rather felt like she had back up. With that back up, she gave Tarkin shit. When Vader put his hand on her shoulder, it felt a little like when her father Bail Organa used to catch her in her childhood. It was strange, very strange. Much to her dismay, opposing Tarkin, had cost billions their lives, at the end of the day. Upon the destruction of Alderaan she felt the shaking of the force, it was horrible, and she regret not having been more diplomatic, maybe it would have changed things.
On Dantooine:
Ahsoka felt the convulsion of the force, too, and she knew, something terrible had happened. Soon thereafter, she was called by Mon Mothma, on her com link, asking her to bring all her available forces, men and ship, to Yavin IV.
The same evening, they were all headed for Yavin IV. Ahsoka, Mike, the 3 Siths, the Padawans, the twins and all their ships.
Rebel base, Yavin IV:
After arrival on Yavin IV she saw the Phoenix rebel team with Esra, Kanan, Hera, Sabine and Garazeb. She was happy to see them and they were happy to see her. She just sensed Kanan still having his doubts about her. There was no time for exchange of stories, because Ahsoka and Mike were called in for a meeting with Mon Mothma and General Dodonna. Dodonna first expressed his gratitude about having provided the rebellion with a star destroyer. He informed them, that it had proven very useful already, even in the short amount of time. With that line, he immediately built a connection to Mike. Next, Mon Mothma let them know that the empire would bring in massive troops and their newest weapon, the Death Star.
Mike was going: "Ah the Death Star, nice piece of imperial boast."
Mon Mothma astonished: "You know the Death Star?"
Mike again: "Yes, I helped a little in building it, I have all plans for it."
Mon Mothma lost all facial features: "You have the plans? Where?"
Mike responded: "Here on this data storage cube."
Mon Mothma got very angry: "Do you know how much it cost us to get hold of those plans, all the while you had them on a data storage cube."
Mike uneasy: "Well, did you ever ask me?"
General Dodonna stopped the two. It had no use to cry over spilled milk. The men, the equipment and the money of the Rogue One mission were lost. It is bad that the plans had already been within the rebel's hands, but now it's all ancient tales, they had to think about how to destroy the Death Star. With his previous bad experience, with Mon Mothma, Mike did not reveal that he could destroy the Death Star any time without big effort. He connected his data storage cube to the holo table in the barrack and explained the complete structure of the DS-1 to them in layman's terms. He pointed out the energy source, the defense systems and the laser weapon. Mon Mothma was speechless, she assured him how much they had sacrificed to get the plans of the Death Star and now it turns out that he had them, knew the Death Star in and out and never said a word. General Dodonna interrupted again, advising her, that obviously the communication with the rebel teams had to be improved, but what matters now, is how they can destroy the Death Star. Mike explained, that one way would be to enter the DS-1 with a brute force attack, simply storm it. Dodonna, turned it down, they would not have enough men and ship to do that. Then Mike pointed out, another way would be for a disguised team to sneak in and destroy the reactor and/or laser weapon. Dodonna liked that idea more. Then 3rd was to bring a torpedo into the ventilation shaft and have it run down the pipe and explode close to the reactor. Dodonna liked that one most.
Eventually general Dodonna wanted to pursue option 2 and 3 at the same time. Mon Mothma asked Ahsoka if she and her team would execute option 2, because they had proven to be excellent in sneaking in. The source urged Ahsoka to decline, it was a suicide mission and her destiny in this battle was another. So Ahsoka declined, telling Mon Mothma when option 3 succeeded, her team would die. She would not lead her team into such a mission.
Mike quickly carved up a plan for the secret infiltration of the DS-1. The team of 20 rebels disguised as storm troopers that accompanied them in the mission in the Hutt system would be brought into the DS-1, then splitting up, 10 for the reactor, 10 for the laser weapon. He would bring them into the hangar section using the Lone Scout, from there they would have to work their way to the reactor and the laser. Then setting bombs with com links. Later they would have to make their way back to the hangar where they would be picked up again. Dodonna would be able to trigger the bombs anytime with a com link. Dodonna liked the plan and had the 20 soldiers called in. Ahsoka did not like the plan at all, not because it was bad, but because it would bring Mike in danger. It was too late now though, she could not stop it anymore. When the team of soldiers had arrived in the barrack, Mike gave them an extensive briefing of the mission. He would again and again ask questions, to check if they had memorized all the details. At the end of his spiel he gave them the access codes to enter the restricted areas. Finally Dodonna ordered them to get ready, in 45min. the mission would start.
Ahsoka used the next 45 min. to be with Mike, she feared, something could happen to him. She thought, the ways of the source are mysterious, she, the mightiest force wielder in the galaxy, needed the back up of Mike the mechanic. Without him, she could not function. She did not mind at all though.
In the meantime, the DS-1 arrived in the Yavin system. With its arrival, the rebel's plans got a much higher urgency. They had to execute Mike's plan immeditatly.
When Mike wanted to enter the Lone Scout, one of the Twins told him she would go with him. Mike informed her that she would better remain with Ahsoka, because he was going on a dangerous mission. The Twin retorted, that because it was a dangerous mission he would need her and Mike understood. She further instructed him to retrieve the R2 MCU in the transport case from the VT-49.
5 more minutes and they were gone for the Death Star. Mike turned the cloaking device on then waiting in vicinity of the Death Star for a ship to enter the hangar. The Twin however advised him to shut the engines down, it was not the right time yet.
Part IV
On the Death Star:
Darth Vader had sensed Obi Wan on the Death Star and wanted his final revenge for Mustafar. Pay-back time at last. At the same time the crew of the DS-1 was searching for the escaped prisoners. In that moment, the Twin instructed Mike to start the engines again. Soon a Tie fighter approached the Death Star and Mike got as close as he deemed OK, then entering through the energy barrier blocking the hangar, right behind it. The Twin advised Mike to bring the Lone Scout to the upper access walkway for the Tie fighters. The Tie fighters were hanging like bats of a shelf system with walkways for each level. The rebels disguised as storm troopers could start their mission from there. With the turmoil, of searching escaped prisoners, going on within the DS-1, they would have it much easier to perform their tasks. Mike wanted to take off again, when the Twin pointed to one Tie fighter. All Tie fighters in the shelf system looked like the standard Tie fighters with their straight 6 edged wings. One however was different, it had inwardly bent wings which did not extend beyond the body. Mike remembered having seen plans for it, when he worked at Sienar. It was the Tie fighter Advanced X1 and must have been relatively new. The Twin requested Mike to reduce the power of its laser canon down to 30%. Mike hurried over, opened the top cover and entered the Tie Advanced X1. He wanted to admire the new design and check out all its new and nifty features, but the force urged him to hurry. He hooked the R2 MCU up to the ships computer, first running a brute force attack, then limiting the laser canon to 30% max. power. When he climbed out of the Tie fighter again, a Tie fighter pilot was on the walk way asking him what he would do in Darth Vader's personal Tie fighter? Mike quickly responded, that he was commanded to retrieve this piece here, holding up the transport case. The pilot seemed to be satisfied with this answer and entered another Tie fighter. Now Mike quickly got back inside the hidden Lone Scout, waiting for that Tie fighter to leave the hanger and thus opening the energy barrier for him.