The next morning, it was confirmed by the Merc Summons sent into the caves that there are numerous Arachnids amongst the intricate and complex tunnels in the mountains. As a pack of 5 tier 3 beasts, they were able to handle quite a few Arachnids throughout the night. Enough to level myself once more. They were unable to traverse to far, however, both due to the increasing density of monsters and how tired they became after traversing and backtracking multiple dead ends. Thanks to them however, we are able to have a preliminary sense of the beginning layout of the tunnels and what paths to avoid. 

Regarding the dangers of traveling into these caves, my biggest fear is probably not the monsters since so far my Merc Summons can deal with the Arachnids, and my even more powerful life summons could probably protect if there was an even bigger threat, rather the idea of no oxygen, or the caves collapsing, or any "danger" that comes with exploring the underground comes to mind. Well, if the Arachnids and my Merc Summons can survive underground for so long, then oxygen is probably not a problem, and so far there haven't been any earthquakes or tunnels collapsing being heard by my summons so the caves may very well be incredibly secure. Another worst case scenario would be some kind of new monster shooting poisonous gas deep underground and getting trapped down there.

Thankfully I have quite a number of useful skills by now. My current list of useful active skills I always keep in mind are Recall, Teleport, Heal, Replenish, Mana Guard, Merc Summon, Communication, Mana Map, and Mana Arrow as a basic way of attacking. Although recently my mana arrow has been showing less effectiveness on the monsters. Instead of one shotting goblins and the like, it takes 3 or so to break through an arachnids tough exoskeleton. These are the main skills I keep in mind to use in case of  a fight. Merc Summon is my main offensive skill, although I generally summon creatures way before a fight even starts, Heal and Replenish help keep my summons healthy and high in mana if they use them. Generally beasts don't use mana, but the elemental variants will so using S. Replenish on a Lightning Wolf will "recharge" its ability to use electricity and spells. Communication is pretty much always used, Mana Map is used like a radar to grasp the surroundings, and Mana Guard is always on so that any attack on myself will instead of affecting my pitiful 13hp, will be directed towards my mana pool of over 290. This essentially ensures that while taking a sneak attack is definitely not a great situation as my mana will plummet, at the very least I shouldn't get one shotted by any enemies, so long as my mana pool is healthy. Recall and Teleport allow me to bring my summons to me, or teleport myself to a summon. 

This is the key part to why I am even accepting the idea of plummeting ourselves into this mountain. Of course I could just continuously send my Merc Summons, but their progress would be slow, and without actual Lieutenants(life summons) guiding them their decision making and ability to vocalize their process and surrounding become limited. I could send a tier 2 Demon which does have intelligence, but the mana cost would be rather high, and would lead to a much slower process as the number of beast summons available would decrease by quite a few if every squad had an intelligent summon leading. Also intelligent Merc Summons are still no match in both power and wisdom as my life summons which even Laos has shown remarkable growth. Laos and Nix already seem to act fully like humans, although Laos has still yet to talk, both are already very capable subordinates able to lead their groups effectively and efficiently. 

With S. Teleport I can teleport myself to a summon, so I could leave a tier 1 beast summon outside, then if we run into danger, I can teleport myself to that summon and use Recall which allows to bring 1 or more summons to my position. Essentially I can teleport myself and all of my summons out of the caves to a single summons position which will be a plan B summon positioned at our camping spot. It is with this safety net that I can confidently plunge into this mountain with confidence. 

"Is everything ready Sigrun, Ciel?"

"Yes my lady" they both replied. 

"Then, with Laos left behind, let us go forth." I am leaving Laos behind, because she is essentially our main guard for our camp, and safety net all in one. On the off chance an enemy attacked Laos can both fight and run away effectively, plus a big part of her fighting style involved enlarging her size which will be strongly restricted by the narrow tunnels. 

For the first km or so into the mountains, most of the monsters have already been cleared by the Merc Summons I both sent ahead last night and this morning. After seeing how successful and useful scouting the tunnels with Merc Summons, I immediately summoned another squad of 5 tier 3 beast summons. This effectively puts my mp regen from 390 minus the 9 summons in total from last night and this morning to 90mp/h.

:(

Our formation is like this so far, Laos is back at our camp on guard duty, two teams of Merc Summons are exploring the caves ahead. Team 1 has-two tier 3 elemental wolves, earth and lighting, along with 1 tier 3 shadow bat and 2 tier 3 earth bears. Team has the same except Ciel is leading them. . This kind of team allows the wolves and bats to scout for enemies, while the bears will be the main fighters. The others can pick off enemies while the bears bear the brunt of the enemies attention. Finally there is our team, the main team composing of myself, Sigrun, and Nix. As such we as the final group begin our journey into the underground.