Sargasso, as the group discovered, was a swamp planet that wasn't as advanced as the majority of the planets in Polaris, save for a number of facilities owned by the Kerchu, whoever they were, but Ratchet, knowing his father, suspected that the facility they were looking for would be buried in the depths of one of the mountains.
"This is a big planet, and there are plenty of mountains to pick from," Autumn commented, speaking as they flew down to the landing area, which happened to be near where the Smuggler had set up shop, though she decided to focus on Ratchet, just to be sure their visit to Rykan V didn't leave any lasting damage to him, "are you sure we'll find the facility under one of them?"
"No, but it seems like the logical place to look... unless the Zoni tell us to search somewhere else." Ratchet remarked, due to the fact that Clank's odd allies seemed reasonable and might show up whenever they needed assistance, like what happened when they were heading for the Halls of Knowledge and when they were on Fastoon, before he landed and they climbed out of Aphelion.
As they walked down to where the Smuggler was standing, to see what he wanted this time around, Autumn found no new weapons, causing them to regroup in front of the figure who had been following them for some time and had helped them a few times, as well as attempted to make some Bolts off of them.
"You sure move quick. Let me guess, you need Leviathan Souls?" Ratchet asked, because that seemed to be the reason why the figure kept appearing before him and the others, he wanted the souls of the powerful creatures in the area, though he had a feeling that the ones they had seen before would pale in comparison to whatever was on Sargasso, one of the most primal planets he had seen.
"Yes, and you might need these launch pads to move around Sargasso," the Smuggler replied, gesturing to a device that was like what they had found on Kortog, when Clank first discovered those new wings, though it seemed to be offline right now, causing him to gesture to a hacking station and a hacker device in his other hand, "this Decryptor can get them going in a pinch, but, as you said, I need something before I part with it."
Since they only had one Leviathan Soul, due to the fact that they had ignored the powerful creatures on the other planets the Smuggler was hunting them on, the group headed out into the surrounding area and found some massive docile beasts who seemed to be grazing at the moment, including a few smaller beasts, but large to them, that stood on two legs and had curved horns to hurt whoever it was fighting. As they expected the serpent monsters they had seen before were now inferior to the larger beasts, though everyone remained on guard as one of the beasts approached them, spreading out to blast it from multiple directions. Sure enough they were able to bring it down and collect what they needed from it, even though they did have to track down a second one, which didn't take long since there seemed to be multiple near the landing area, so everyone separated into smaller groups and brought down their targets, just to ensure that they had all the souls they needed to buy the device. After clearing out the area of enemies, and gathering the souls necessary to buy the Decryptor, everyone regrouped and Ratchet made the trade, allowing him to hack into the nearby terminal and power up the platform that would allow him to use Clank's brand new wings.
With that done he and Clank took off, his friend sharing his sight with him so he could figure out where they were going, all while Autumn and Starswirl used their magic to lift everyone else, following behind them as Clank tracked down the Zoni's trail, though at the same time Autumn found a fragment of the RYNO 4, which she pocketed for later.
As it turned out the trail brought them to one of the Kerchu's buildings, who opened fire on them immediately, without a moment of delay, causing the group to wage war with them in kind, all while Autumn tore apart the spherical armor that a few of them were wearing with her sharp claws, finding that she really liked her new power. There were also some native creatures who wanted them dead, small red bugs who basically died in the crossfire between them and the Kerchu, but it didn't matter as Ratchet and the others blasted their way through their enemy's forces before he hacked into the building so they could move forward. As the group discovered the building didn't have anything for them, save for obstacles that all of them overcame in no time at all, before finding some platforms that allowed them to enter a rundown building, which just so happened to have an ancient Lombax weapon inside it, the Alpha Disruptor, a nano-weapon that fired beams of plasma at the target. Such a thing allowed Ratchet to rapidly take down one of the larger beasts, in three hits as opposed to what they were used to, and he knew that when they left Sargasso his sister was going to tinker with it before figuring out how to upgrade it and get it approved by Gadgetron, before finally finding a cave that seemed to be where they were to be going.
In the heart of the cave they found a facility that seemed to be their final destination, for now, and Ratchet hacked into the terminal to open a door up, allowing them to enter another Lombax facility, before finding a wall that opened up as they approached it, revealing the Plumber, who was slightly older and had glasses on his face, tending to an odd machine, one that wasn't the Dimensionator.
"Oh, it's just you guys... almost didn't recognize you, since we haven't seen each other in years." the Plumber said, where he seemed happy to see them, and for the most part the majority of the group felt the same way, though Ratchet was the only one who wasn't even remotely happy, given what happened to his sister, "You guys seem disappointed... let me take a guess, you were expecting to find a gadget that's capable of vaporizing an entire planet of Cragmites?"
"Please, don't insult our intelligence. We already know about the Dimensionator and that it allows one to move through dimensions, meaning the Cragmites were moved." Starswirl replied, as they had figured it out long before reaching the facility on Rykan V, thanks to him and Autumn figuring it out and Aphelion informing them about the device, before he and the others found that Ratchet was moving towards the Plumber.
"You would be correct." the Plumber stated, though in the following moment he found that Ratchet was annoyed with something and he suspected what that something was, given all of the questions he had asked in the past, whenever they crossed paths, and he was ready to answer whatever he asked this time around.
"I don't want to hear you say 'she's safe' this time around. We know Rivet's hurt! I woke up screaming the night before we were attacked by Tachyon, feeling like my arm was blown off!" Ratchet stated, though none of the others tried to stop him, as they knew he was annoyed and that he could have prevented this if the Plumber had bothered to help him save Rivet, before she was harmed by whatever had struck her, "You said your son was watching over her... well he failed to keep her safe, unless his job was to just observe and not interact with her... so I don't want to hear any excuses. Clearly you know about the barrier between dimensions and are able to traverse them with some ease, so I want you to open the way to my sister and let us assist her."
As the Plumber opened his mouth, to say something to calm Ratchet down, he paused as he felt the dimensional energy surge through the chamber and a crack in reality appeared nearby, showing them what looked like someone's home, and Ratchet found Rivet, minus her right arm, resting against a wall as she stabbed her wound with another needle, as there were several around her, and drugged herself to dull the pain.
"You see? She's hurt!" Ratchet continued, though it pained him to see his twin in such a state, hurt so much that she had to resort to such a thing to dull the pain before doing anything about her arm, causing him to turn on the Plumber, who was just shocked by what they were seeing, meaning that, despite his ability to see everything or whatever it was, this was something he wasn't expecting, "Do something!"
"I can't. You must understand, assisting you in small ways is all I can really do." the Plumber replied, where Ratchet wasn't the only one pained by the scene in front of them, in fact he felt sorry for Rivet as well, but there were rules he needed to follow and if he helped Ratchet now, in the way he wanted, it could have disastrous consequences for everything.
"Screw this." Ratchet said, as he couldn't believe what he was hearing, that the Plumber couldn't help them, or maybe he didn't want to given the fact that he refused to help him find his sister every time they encountered each other, though in that moment he walked up to the crack and pounded on it, finding that it was more solid than what he, Starswirl, and Autumn had assumed it was, "Rivet! I'm here! Your brother's here for you!"
For a moment it didn't seem like he was doing anything other than wasting his energy, though that was when Rivet lifted her head and noticed the crack in reality that they had spotted, allowing her to see Ratchet fully this time, instead of her seeing the armor he had been forced to wear during their time under Vox's thumb. Autumn and Starswirl tried to use their magic, to aid their brother, but the Plumber shook his head, indicating that mixing dimensional energy and magic wasn't a good thing, meaning if they used the Dimensionator they couldn't use magic for a time, causing them to watch as Ratchet smashed at the crack with his fist and his wrench. He kept calling for Rivet as he did everything in his power to break open the crack, as she was literally in front of him and he wasn't about to let this chance slip him by, while Rivet watched him for a few moments, either because the drugs were messing with her or because she doubted what she was seeing, before his necklace fragment fell out into view. In that moment Rivet lifted her left hand and reached for her neck, pulling out the other half of the charm they had been given by their parents, something that caused her to stand up and start making her way over to the crack, just in time for something truly marvelous to happen.
Ratchet, channeling all of his determination and power, punched the crack in reality and it shattered, like a window that had been broken by a rock, though when he tried to move forward he found that he couldn't, something was blocking him from crossing over, to which he reached for his sister, to help her cross over... but as they tried that, however, their fingers touched for just a second before the crack repaired itself and Ratchet was bounced back into the arms of Angela and Sasha, only when he regained himself he found that the crack was gone.
"No... nonononono! RIVET!" Ratchet called out, hoping that something, anything, would take pity on him and his sister and bring the crack back so he could save her, but as he staggered forward he found that nothing was there, the crack was gone and so, too, was his wounded sister, causing him to fall to his knees as he pounded the ground, letting his tears fall while he did so.
As the Plumber handed Autumn an item, a three and three fourths cubit hexagonal washer that they'd need later on, he realized something, if it hadn't been for the untimely interference of another being, who was also watching over Ratchet, the Lombax would have done the impossible, he would have saved Rivet and would have brought her home, but now all he could do was leave them to tend to Ratchet as they faced whatever the future held for them.