Sam learned about the behavior and characteristics of these sea urchins in every possible way he could think of.

Now, he has to make something that could effectively defend against these things and repel them away if possible. And he shouldn't forget about the harpoon guns and the flat-fish puppets.

The harpoons they shoot are also going to be a problem.

But he is a bit relieved by the fact that the harpoon and the sea urchin are a bit similar in their attacking method.

The only main differences are size and shape and the spikes of the sea urchin cannot be defended with water elemental attacks and the last difference being the trap and cable mechanism of the harpoon gun.

The propelling principle is almost the same. But instead of a compressed air contained that is used in the harpoon gun, the sea urchins are creating compressed gas propulsion by themselves.

Sam could think of a few ways to counter these things. The main principle of these projectiles is the usage of gas and air underwater.

So, Sam decided to use this as a counter too.

He doesn't even have to stop the harpoons and spikes moving all he has to do is deflect them away.

Make them not continue in the same path and because of the compressed air or gas propulsion there is one thing they could take advantage of and that is the fact that the trajectory of the harpoon or the spike cannot be changed by the shooter once it was shot.

They cannot manipulate it constantly.

And this gave Sam an Idea.

Using the same compressed air to change the trajectory of these things.

But before he could make anything, he has to inspect the city first. Since the merman can activate multiple elements and that includes the fire element, they do have the ability to maintain decent craftsmen in their ranks, but sirens are different.

They don't activate any other element. They only have the water element and that unbearably good mental strength and attacks. They might be good with their hands, but they are still unable to create proper weapons faster. If they have to go for the weapons, they had to go the old-fashioned way.

Placing the metal in a normal furnace and hammer it constantly with no control over the heat would take up too much time and also sirens wouldn't want to spend too much time near that fire. They would die if it is too long.

But selling the weapons directly to the sirens from the above-ground is not exactly a good deal. In fact, it impossible. The Elves would kill him before they let him export weapons to the sirens.

So, he has to see how he can manage to properly cut this deal.

After four days of constant research, Sam came out and met with the attendant he was assigned to.

"I would like to take a look at the city. Particularly the volcano."

The attendant nodded and gestured Sam to follow him without saying anything. Sam didn't mind and just followed him.

He walked through the streets as he looked at various things that are being sold, made, and worked.

It is very little for sirens to do. Their staple food is obviously the fish in the sea, apart from that they train a lot, they rear some things like a special type of seaweed and another thing is the mining.

They excavate under the sea and also mine the spirit stones from the spirit stone mines nearby.

Other than these common things, there is only one uncommon and unique thing in this place and that is making products for the elves on the surface.

These people make some products of the things they get under the sea.

They make potions of different kinds right in this city before selling them. And the main ingredients are obviously from the sea creatures and some scarce vegetation that is available on the seafloor.

Even with minimum work, everyone is active and they are all currently looking at Sam as if they are looking at an animal in the zoo.

"How many Siren cities are there?"

"There are forty cities that are of decent sized. And this is the Siren Capital.

Apart from the cities there are some minor establishments within the sea with a smaller population of sirens."

The attendant spoke for the first time.

"So, only Capital city has access to meeting with the surface."

"No, according to the treaty between elves and sirens, the sirens belonging to all the forty cities can go to the surface to conduct any business. But the sirens who do that are rare and even they do it in a specific time period every year.

The sea is mostly sufficient for our survival."

Sam nodded and both of them continued.

The attendant started leading him into an alley and spoke.

"The route to the volcano is a bit remote and there would not be many people there."

Sam was a bit confused but he still nodded. After all, it is not necessary to make himself clear, it is not like Sam is extremely suspicious of the attendant.

When this thought came to his mind, he immediately halted in his tracks and looked at the attendant with a frown.

The attendant who is walking in the lead noticed that Sam's footsteps are halted and stopped too.

Sam closed his eyes for a second and a smirk appeared on his face.

He started walking forward with that smirk and he started speaking with the attendant.

"Have you seen these sea urchins? The ones that are attacking your kind near the island."

"No, by the time I was deployed to train there, it was already infested with the sea urchins and they are already attacking us."

"Then let me show you something."

Sam took out the spikes of the sea urchin from the storage.

"These are the spikes of the sea urchin. You can imagine just how big they are. But they are still good at stealth."

The attendant looked at Sam with confusion.

"They are too good at stealth, they can blend into rocks as if they are part of it, they can bend their spikes and make it look like a flat surface without even exposing themselves a bit.

They shoot the spikes at an incredible speed and it would be too late before you even notice it."

The attendant was even more confused. But he still nodded.

"I still survived them without taking much damage, do you know why?"

The attendant thought for a second and said.

"You are strong?"

"No, I am good at finding the hidden things. They might be objects, beasts, and creatures like these sea urchins or even the Sirens that are hiding in the alley."

The attendant stopped in his tracks and gulped. He looked at Sam with his eyes wide open.

"Come on, let's walk and talk."

The attendant walked carefully, he is worried that Sam might do something. After all, Sam knew about the people hidden inside but still came.

Sam tossed a spike and caught it and he played like that for a few steps before throwing it in a direction. The spike pierced into a stone wall and almost penetrated to the other side, but halted right before stabbing into the siren.

Sam took out another spike and threw it in a different direction. He repeated this process as he walked.

"I could guess who made you do it. But the next time you do it, remember one thing. This time spikes stopped at the last second, the next time it wouldn't be the same. I have to respect the hosts as a guest, which is why I am leaving you guys alive. If you do it one more time, get ready to be killed."

The attendant became nervous.

"I am really sorry. But I was forced to do it. That person is a son of a powerful person and they are not here to kill you. They wanted to teach you a lesson…"

"What is the point of the explaining now? One has to bear the consequences to their own actions. No one can completely force others to do something. It was all a choice. Maybe he threatened you with your family, but that is also your choice to go with it, after all I am sure you have laws and rules, you could have gone through the legal way.

But you didn't, because you are afraid or worried or even became greedy for the reward.

Anyway, I already said, this time I am not doing anything to you. But that doesn't happen the next time. No matter what you are forced to do, that is not my business. Being compassionate is not my cup of tea."

The rest of the journey was silent. He was lead to the volcanic area.

The area is similar to what Sam guessed. They opened up the soil within this bubble and let the Lava create a pool and there is a large formation covering it. The formation seemed to be a temperature controller as the heat is not as intense as Sam thought.

They even created small currents from the pool and led the lava to create even smaller pools which are covered by formations and these are also similar to the main formation but a bit different. These formations can hold the container in place and some sirens are concocting something in this container.