Jak and Pinkie walked out of the elevator and found that they had two paths to choose from, one of the left and one on the right, though the one to their right had several vents that were spewing some sort of toxic gas every now and then, to which the siblings decided to head to the left. They approached the door that was in front of them and waited for a few seconds, though they rapidly discovered that the door was actually locked, which meant that they would no doubt be using that particular path at some point in the future. Since they only had one other option available at the moment, besides returning to the surface, they walked over to where the vents were and waited for the gas to turn off, to which Jak went first and eventually reached the other side without hurting himself... to which Pinkie happily smiled as she repeated the same movements and landed by her brother.
They stopped by the ammunition crates that were near the last vent, allowing Jak to restock anything that she had spent on the ride here, before they opened the door and opened fire on the KG robots that were on the other side... or at least Jak opened fire on them, because Pinkie shifted her weapon back to its blade form, as the scythe was too large for the area they were in at the moment.
As they turned the corner they spotted a gap between where they were standing and the area they needed to walk through, though the only way to reach that area was to use another pathway made out of vents, to which Jak and Pinkie shot down the KG robots that were patrolling the other side of the chamber they were in. Once the robots were dead, and they were sure that there weren't any additional foes to face at the moment, Jak used the vents to reach the upper area, where he blew apart the fan that was in the water while Pinkie crossed over. The moment Pinkie was up there they jumped over to the walkway one of the robots had been walking on and followed it to another pair of vents, though around the corner they discovered a passage that had a few KG robots waiting for them.
Before they moved forward they made sure to eliminate every enemy that was around them for a moment, pausing to make sure that more didn't show up, before they walked down the steps that were in front of them and jumped onto a moving platform. As the platform moved they had to jump over two moving laser beams and shoot down some flying robots, though when they came to a stop there were two more enemies for them to take out before they were allowed to turn around the corner. As Jak walked forward Pinkie noticed the electric pillars that would form an electric fence that was designed to keep the two of them from retreating, to which she decided to try out the new Gyro Mod she and Jak had acquired from Tess.
Not a few seconds later, when they had both walked passed the pillars, the fence turned on and their enemies flew up from the abyss in front of them, with the intent on killing them.
"Jak," Pinkie said, to which both Light Eco and Yellow Eco flowed in front of her body for a moment, though she could tell that her brother was looking at her, "Throw up a shield."
Jak nodded and his Light Eco Shield phased into existence, to which Pinkie grinned as she used her Yellow Eco to launch a Gyro into the air, though as it started to fire she snapped her own shield into existence as well. The two of them watched as the spinning Gyro started firing blasts down at their enemies, dismantling them and scattering their parts everywhere. When all of their enemies were dead, and they had dropped their shields, the fence in front of them powered down and allowed them to press onward, only for them to walk into another section of the walkway that was being guarded by more of the KG robots. This time they weren't attacked by a group of the flying enemies, rather they were attacked by a large group of the smaller robots, the ones that clattered on the ground and shot electricity at them, but when Jak loosed a Gyro burst their enemies fell.
When enough enemies fell the fence in front of them powered down and they jumped onto the moving platform that they needed to use in order to access the other side of the chamber they were in, though in addition to avoiding a laser beam they had to out maneuver a machine gun that was firing at them. It took some time for them to reach the area where the machine gun was located, though when they reached it, and jumped behind the gun, the weapon powered down and allowed them to move through the door on their left. When they jumped down into the area below them they were attacked by a large group of water type Metal Heads, the Saw Fish type according to Raven... who quickly advised that they avoid the sharp noses of their enemies.
After a few moments of fighting, and they were sure that their enemies were defeated, Jak and Pinkie dived into the water and swam under the barrier that was trying to prevent them from moving forward, though when they jumped out of the water they were under attack once more. They simply repeated the process they had used earlier, which was shooting their enemies before they got to them, before pressing the button that was on the walkway next to them, one that opened the doors in front of them. The next area they walked into had a number of moving platforms moving around the exterior of a metallic cube, which happened to have the same layout on the other side of the wall they were staring at, and there were two KG blade bots moving around the area.
Pinkie, seeing the blade bot, held her blade out as she waited for the robot to come back towards them, though when it did she jumped onto it and drove her weapon into its head, aiming to damage the systems as Jak made his way around the exterior until he found an opening. When Jak reached the opening Pinkie drove the robot she was driving into a wall and followed after her brother, where she did the same thing with the second blade bot that they discovered, though when Jak entered the middle of the cube he discovered a button that opened the door they needed to pass through. The doors they had originally walked through closed on them and a new one opened, to which they followed the new way out of the cube and jumped onto the platform that the way forward was located on.
When they jumped up to the platform, and turned the corner, they discovered a door that opened up to a wide room that had a large hole in front of them, though instead of focusing on the hole they targeted the flying KG robots that were trying to attack them. They fought their way along the pathway that was in front of them and found another door waiting in front of them, though this one possessed an elevator that they immediately climbed onto and rode to the surface... though when the door opened they found themselves in the Metal Head side of the city, which looked like a whole different world than what they were used to.
"Jak, Pinkie, this is Ashelin." a voice said, to which their communicator came to life and floated around them for a few seconds, though at the same time Pinkie and Raven looked out for enemies, "I'm glad the two of you are back in the fight. You're behind enemy lines now, so watch yourselves. I need you to take out a cache of Dark Eco near the South Port border. We have reports that the Metal Heads are using it to create terrible Dark Eco weapons to infect the city. We've got to stop that at all costs. Good luck and stay safe."
As Jak and Pinkie walked into enemy territory they discovered that the walls were bright green colored, with metal spines running up and down at even intervals, while the floor they could walk on was green and grey colored. Below them was a wide pit filled with a shimmering green colored acid, which was also bubbling when they looked at it, but at the same time the siblings agreed to avoid falling of the edge. They also noticed that there were spires scattered throughout the acid pit, all of which of a variety of sizes, though some of those spires had sparking Dark Eco Crystal formations at their peaks... which had to be what Ashelin wanted them to destroy.
The group carefully made their way around the walkway that they had stepped out onto, while at the same time they started searching for a path to take so they could reach the Dark Eco Crystal formations, though as they moved they were attacked by the Metal Heads that called the area home. Fortunately Raven didn't seem to mind the area around them and used his hybrid form to rip into the enemies that were coming at their backsides, while at the same time Jak and Pinkie focused on the enemies that were in front of them. Pinkie noticed a thin purple cable of some sort connecting the walkway they were on to one of the platforms above the acid, to which she pointed it out to Jak.
Her brother studied the purple cable and nodded his head, to which he switched his gun for his jet-board before he used it to grind over to where the platform was waiting for someone to climb onto it. He looked around for a few seconds before he found some sort of flower that was expelling some sort of gas, where he discovered that he could use the short bursts to ascend to where the crystal was waiting. Jak then smashed the crystal with his fists, though once the crystal was in pieces he jumped back down to the platform below him and used his jet-board to ride the purple cables to the next area... all while Pinkie fought her way through the walkway with Raven at her side.
Pinkie made sure to keep an eye on what Jak was doing, because he had to traverse a number of purple cables and launch flowers before he could reach the second Dark Eco Crystal formation, though while he did that she cut down the enemies that were in front of her. After the second crystal fell Jak returned to the walkway, thanks to one of the launch flowers he came to, to which both he and Pinkie launched themselves forward and found the third crystal at the top of another spire. Once that one was destroyed they continued launching themselves around the area and eventually came to a stop in front of the fourth crystal, though once they had smashed that one they discovered that the next launch flower would have tossed them near the acid pit.
Instead of taking a chance, and possibly hurting themselves in the process, Raven morphed into his dragon form and let Jak and Pinkie climb onto his back, to which he flew them over to the fifth crystal... though when that one fell a sixth crystal sprung up near a wall, with a large amount of Dark Eco flowing in the air around it. Raven landed near the crystal and let Jak and Pinkie approach the crystal, though when they smashed it something interesting happened; the Dark Eco caused Jak to transform into his Dark Form, to which he gathered the excess energy into the area between his hands and released a burst of power that smashed the wall in front of them to pieces. Pinkie, on the other hand, didn't seem to notice any change to her body, though as Jak returned to his normal form he noticed that his sister was playing around with the Dark Strike ability he had just unlocked... though he suspected that the Precursors had done something to Pinkie when they went through the second door.
He also noticed that the wall he had smashed down allowed them to have a shortcut back to the port, though at the same time he spotted the Neo Metal Heads standing some distance away from the opening, indicating that they were waiting for enemies to approach them once more.
"Jak, Pinkie, this is Samos." their communicator said, to which the siblings looked at the communicator once more, though they were all glad to hear Samos' voice again, "While you're near the entrance to South Haven Forest, could you please go check out reports of a Dark Eco infestation there. It seems someone is still experimenting with Dark Eco. If you find infected plants, you must destroy them before they spread. There are some ancient Precursor pillars in the forest that may have a link to the catacombs, but if the Metal Heads overrun the place, we'll never know for sure. Make me proud!"
Jak and Pinkie looked at each other for a few seconds, as they were both wondering what had happened to the forest since they had last been there, but instead of spending too much time thinking about it they quickly made their way towards the entrance. After they passed through the security doors they discovered a Green Eco Vent some distance in front of them, allowing them to restock their health while Keira reminded Jak that his jet-board had been modified to carry and disperse Eco. Jak jumped onto the jet-board and started riding around the area, leaving Pinkie and Raven to sit on one of the rocks and watch him work, as Pinkie had nothing that would allow her to do what her brother was doing... though she did have to contend with some hostile creatures that wanted to hurt her, which she killed with her Scatter Mod.
It didn't take Jak long to finish treating the Dark Eco plants, though when he returned to where Pinkie was waiting a set of five pillars, which surrounded a larger one, broke out of the water near them, but they remained close to the surface of the water.
"Great work you two!" Samos spoke up, indicating that he had seen what they had done, or rather what Jak had done, and was praising their efforts, "Those Precursor pillars are some of the oldest artifacts we've ever found. Mar wrote that there was some ancient ruins to the west that were activated by five special artifacts and revealed wondrous truths. I'll see what I can find out."
Jak and Pinkie simply investigated the central pillar and found another shoulder piece of an armor set, which Jak immediately attached to his right shoulder, before the two of them departed from the area. They were sure that, at some point in the future, they would find the five artifacts that Samos had told them about and discover what sort of truths the pillars had to show them... though they were also sure that Torn had another mission for them, to which they smiled as they walked towards the doors once more.