Rockworm leads the way.
Eventually, you will leave the tunnel and go through one of the tunnels that the rockworm seems to have dug.

The tunnels are as big as a man, so there is no reason that a man could not walk through them.
However, the height of the tunnel was as cramped as that of a dwarf tunnel.

On the other hand, the width of the tunnel was clearly narrower than that of the mine.
In the tunnels, we had been moving in double file, but now, as we entered the Rockworm tunnel, we were moving in single file.
Because I was the controller of the Rockworm, I was in the front row, followed by Satsuki, Mee, and Cyril.

'Wow, ...... there's something slimy and sticky around my feet and on the walls. ...... Whoa, something's dripping from above!

'Nah, it doesn't look like it's going to do any harm, but it's not a place I want to stay in for long.

'I want to die. ...... I want to go home and take a bath as soon as possible. ......'

Surprisingly, Cyril was the one who whined the most.
No, before he whined, he actually sounded like he was whimpering from behind.

Apparently, he's really not good at it.
Even so, he didn't insist on following us, which is a good example of self-control.

After a while, the rockworm in front of us stopped moving.
Due to the narrowness of the tunnel, the rockworm could not look back, but it seemed to be trying to tell me something by moving its tail.

I turn around and tell my friends.

'We've probably reached our destination. ...... Are you okay, Cyril?'

'Gosh, ...... I'm not okay, but I'll do my best.'

Cyril at the end of the line had tears in his eyes, but he seemed to be clenching his teeth and holding it together.
......Well, since he says he's going to do his best, I'll trust him for now.

Well, anyway.
It's probably a good thing that you've reached your destination, but the Rockworm that's controlling you is in the way and you can't see what's going on.
What should I do?

'Rockworm, can you clear a path? I don't want your people to notice.'

That's what I'm going to tell them.

Rockworm then proceeded to bite through the wall at his side and evacuate himself in that direction.
...... I see.

When the rockworm that had been blocking our path was gone, I could see what lay ahead.
I took a few more steps and looked at what I saw.

'This is a ...... surprise. In a way, it's quite a spectacular view.

'What, what, what, I want to see it too. What the hell is that?

Satsuki came up behind me, looked over my shoulder, and immediately shouted in disgust.
I could understand why she would want to do that.

The Rockworm tunnel we had come through led to an open underground space.

It was a mortar-shaped space, but it was so vast that it seemed as if the walls of the royal castle of Greysburg could be completely contained within it.

We are now in a position overlooking the mortar-shaped underground space.
If we exit the tunnel we are in and go down the steep slope, we can reach the base.
From your current position, the ceiling is rather close, and if you use the levitation spell to surface, you will be able to reach the ceiling where stalactites hang down.

In addition to the tunnel we're in, there are a number of other 'holes' in the outer wall of the underground space.
Rather than being connected to this space from a number of tunnels, it's probably more appropriate to think that this space is the result of Rockworm digging tunnels here and there.

In that vast underground space, there was a large number of things moving around.
Like Satsuki, Mee poked her head out from beside me, and raised her voice.

I'm not sure if it's the larvae of the rockworm ......? I'm sure there are more than ...... thirty of them. Maybe there are forty ...... or even fifty?

It's not as big as a larva though. But it's true that they're about half the size of the ordinary rockworms we've been seeing since yesterday. But even so, it should be able to swallow us whole and put us all in its stomach.

As Mee and Satsuki said, at the bottom of the underground space, a large number of small rock worms were wriggling around.

But even though they were small, their total length was about fifty percent of a man's height, and if they opened their mouths they could probably swallow a man whole, headfirst.

Incidentally, one of them didn't respond, so I looked behind him and saw Cyril there, frozen like an ornament, shaking with tears in his eyes.
I don't think we can see much of the underground space from that position, but the content of what Satsuki and the others are saying may be enough to ruin us.

Well, let's not worry about Cyril for now.
She won't play a decisive role in this mission.

Me and Satsuki, on the other hand..,

'But the adult insects... are there any that you can see?

'Looks like it. Are the adults migrating to find food?

'It's possible. But I'm sure there are a few of them left to guard the larvae.

'Hmm, but even the larvae seem to be stronger than most monsters. It doesn't need an escort, does it?

'Maybe so, but ......'

Mee looked a little confused as she thought about it.

I was rather concerned about the same thing as Mee.
In other words, there might be a 'guard' hiding somewhere.
At the very least, we should keep that possibility in mind as we move forward.

'I'll use the wizard's eye to scout. Please wait a moment.

I used the spell of the wizard's eye, which has become a standard spell, and brought the transparent 'eye' that appeared in front of me out of the tunnel and into the underground space.

Incidentally, while I was concentrating my mind to advance the eye, I could hear the conversation between Mee and Satsuki.

'Satsuki, do you know how amazing this wizard eye is? You don't have to actually go down there to find out what's going on, that's how amazing it is. You don't have to put yourself in danger. That's a foul thing to do, isn't it?

'I know. I know how great Will is. I know that better than anyone!

'Are you sure? I think Mee understands William's greatness better than I do.

'No, I don't! I know what I'm talking about!

The two of them were arguing over something strange.

But I've heard that it's surprisingly difficult to find a friend who appreciates the value of your work.
I think I am blessed with good friends in this respect.

Regardless, I'm going forward with my 'eyes'.
I keep it floating at a height of about a meter and a half above the downward sloping ground - the height of my eyes - and slowly move it forward and down along the mortar-shaped ground.

Then, as I move my 'eyes' forward, I look at the tunnels here and there, carefully checking for any hidden rockworms.
There doesn't seem to be any, but...

But there they are.

When we were very close to the bottom of the mortar, where the rockworm larvae were wriggling in large numbers, we found the horrible monster lurking in a large tunnel near the base.

It looked like several rockworms bound together and glued at the tail.
To put it another way, it looked like a hydra.
From the body of the Hydra, countless long tentacle-like appendages sprouted and wriggled.

That must be the Mother Rock Worm.
It was a good thing I had done my reconnaissance.
I shudder to think that I would have attacked without being aware of its existence.



I then looked around the other tunnels with my 'eyes' to make sure nothing else was lurking, and then I released my mental focus on the wizard eye and brought my consciousness back to myself.

My vision returns to peering into the underground space from inside the tunnel.
Satsuki and Mi are beside me.

I stroke her head half-unconsciously.

'Mee, bingo. We have guards. And a hell of a lot of them.'

'No, no, no, no, no, no. ......? Oh, by the way...

'Ah, what appears to be a Mother Rockworm was hiding. It also matches the shape of the one described in the adventure story.

I said, and told my friends what I had seen with my 'eyes'.

Incidentally, behind me, Cyril, who heard my explanation, shed tears beyond tears and said, 'Hiccup, hiccup......I want to go home soon......Dad... I can't wait to go home....
The ...... thing might be really useless.

On the other hand, Mee, who heard my story, asked me with a thoughtful gesture.

'I'm afraid I don't know how strong the Mother Rock Worm is,....... You don't know the monster rank, do you?

'Ah. It's such a rare species that it's not even listed in the Monster Encyclopedia. It's not even listed in the Monster Encyclopedia.

In general, monster ranks are determined based on discussions between researchers of monsterology and adventurer guild raters.
In other words, the ranks are determined by human beings, so they may be wrong, or they may not be determined at all if the monster is rare, as in this case.

A common pattern among monsters is that the rank of the leader of a group, the so-called "boss", is two or three ranks higher than that of the general species of the monster.
For example, an F-ranked goblin mage or an E-ranked goblin lord is the boss of a pack against an H-ranked goblin.

With this in mind, it is reasonable to expect that a D-rank Rockworm boss would have a strength equivalent to a B or A rank.
However, this is only a generalization and a tendency, and there is no guarantee that this is the case.
In some cases, it is possible that an Orc Emperor who is four ranks higher than an F-rank Orc is leading an army of F-rank Orcs.

In any case, it is dangerous to attack a monster of unknown strength carelessly.
I want to measure the enemy's strength by some means before I send Satsuki in.

One idea I had was to lure the Rockworm, which is controlled by a Tame Monster.

But that was quickly dismissed by my brain.
Even if you tell it to kill its parents, it's unlikely that Rockworm will follow your instructions.

So...

'Then I'll use this.

I muttered to myself as I placed my hand on the rock wall of the tunnel.