Realms of Eas

[You have been summoned.]
[You have gained control over the summoning ritual.]
[You have entered the unnamed dungeon in the Forest of eternal Twilight.]
[You sacrificed a High Human Lv 117.]
[You sacrificed a Human Lv 102.]
[You sacrificed the Staff of the Archmage.]
[You sacrificed a Human Lv 105.]
...
[You sacrificed a Twilight Grass Lv 3.]
[You sacrificed a Twilight Tree Lv 16.]
[You sacrificed the unnamed dungeon in the Forest of eternal Twilight.]
[You learned the Sacrifice skill.]
[You gained the title Dungeon Destroyer.]

[Your Searcher of ##### class has reached Lv 1.]
[Your Searcher of ##### class has reached Lv 2.]
...
[Your Searcher of ##### class has reached Lv 18.]
[You have reached Lv 1.]
[You have reached Lv 2.]
[You have reached Lv 3.]

While all the appearing messages were somewhat distracting, they weren't as distracting as the scene around the twins. Sarah was still processing the last message they got in that weird space before they were brought here, but pushed it to the back of her mind. First of all she finally stood up and hid behind her sister, fighting with the impulse to pull her hood deep into her face. She wanted to hide from potential unwanted company, but couldn't risk it to further reduce her field of vision. Then she started to observe their environment.
A stone floor was under their feet. Admittedly, this wasn’t very surprising, since Eas had written that the Realms were similar to their old world, but it was still good to see after their latest experience.
Over ten people were lying on the ground in puddles of their own blood, Sarah assumed, that there were even more which the two couldn't see due to dense fog shrouding their sight. As the puddles were still growing she could only assume the people lying around became like that just shortly before the two arrived. Taking into account all the messages about sacrificing humans, it wouldn't be that far fetched to assume those were the sacrifices. Furthermore, as no other living being seemed to be around and since she was the one who got credit for the sacrificing... She sacrificed their summoner?

[Sacrifice]
[A rare skill normally used to sacrifice your own health as well as enchanted items to substitute for mana in times of need. However your boundless greed for more let it go beyond that which is widely seen as acceptable, even sacrificing others to fuel your ambitions. Allows you to convert other resources into mana, from yourself, enchanted items and even other beings.]

That would at least be the most logical conclusion. Though Sarah wasn't quite pleased with the result. It kind of worked with their plan. From the beginning they intended to flee from their summoners, get rid of them if possible in the process, and gather information. However they didn't have any sources of information remaining and furthermore she couldn't be sure they involved Hannibal, who wanted to bind them with the unreasonable contract, in her unexpected massacre.
Hopefully whoever found this place just thought that the summoning went wrong or a third party intervened, otherwise things could get even more complicated. Being overestimated as a powerful mage was the last thing Sarah wanted in their current situation.
The scientist pushed the thoughts aside. She couldn't change what had happened, therefore there was no reason to think about it. Sometimes she nearly envied her sister for her more carefree personality.
Nearly.
But now she had to collect data.

Confused over the current situation her sister finally broke her shocked state enough to ask Sarah, "Any idea what is going on here? I was expecting a lot but not that we were summoned to a silent battlefield."
"I also didn't expect this... Especially since spells, which interacted with the fourth space dimension, never worked back at home. But even then, the callback to get more mana to stabilize and increase the time dilation, add another person to the summoning, gain us physical and mental invulnerability for a few minutes, displace our summoning location a few meters behind our summoner outside and above liquid and solid matter, as well as create some fog should only do that. Well, i mostly have casted small scale spells until now, so i don't know how much mana would have been actually required for all those extras. Therefore, after taking the mana from the environment, the spell probably continued to search for more mana and took it from those people. I would need more beings who were willing to summon us and another of my bracelets to verify it, but that sounds pretty logical, based on the messages i just got," answered the scientist quietly. She didn't feel well with other people around, which weren't her sister. Those around them seemed dead, but she also couldn't be sure that there were a few lucky survivors without checking everyone.

...
A moment of silence passed while Sera was mentally fighting with the gained information, before giving up. "... and now for mortals?"
"Hm... in a nutshell, i probably added to many extras the summoning, therefore those people were used as fuel? Something like that."
Another moment of silence followed.
"Anyway, we should get out of here before the fog vanishes and potential reinforcements arrive. The people i sacrificed were around level 100. I don't want to know who could still be around. And i don't want to personally experience what a level 100 being could do to a level 0 or 3 one."
Sera could only agree to that. Her frustration over the sudden summoning was mostly buried under her excitement. She still liked to fight, but having multiple enemies 100 levels above her as her first opponents in this world? Yes, that sounded like a bad idea. Though there was still a question. "In which direction should we go?"
Without thinking much about it Sarah pointed to the corpses in front of them. "That way. If we are lucky, we could find the spell circle they used to summon us which should be near the caster."
Sighing the warrior started to walk. "What happened to the plan to get out of here as fast as possible?"
"We don't know which direction to walk anyway and me getting the knowledge about a functioning multi-dimensional transfer spell will help us in the long run. Besides, a few moments will be enough for me to memorize it."
Following Sera who had now a box with [Human Lv 0] in it floating next to her, the two girls carefully maneuvered through the sea of gory corpses with a few islands of rocky floor. Though while being careful, Sarah still needed the help of her sister in more than one instance to keep her balance.

A few meters away from the first group of corpses the scientist caught a glimpse of some lines carved into the ground. They were now filled with the blood of some armed people, who were lying motionlessly nearby. Getting closer they could see a chunk of the circle, but another part was still hidden in the fog. It seemed impossible to view the whole circle without stepping into it. Something neither of the two twins wanted to try out. "Tsk... Maybe i should have cut the fog from the bracelet..." muttered the girl to no one specific, not that anyone besides her sister could have heard her.
While the scientist was walking slowly around it to burn the image of the engraved spell into her mind, her sister decided that she could quickly check on one of those people lying near the lines. Primarily to get another weapon, she still had her own sword, now in its scabbard at her waist, but she wouldn't decline additional ones. Also she wanted to make sure the people were actually dead. It was true that everything told her that they were dead, but after fighting against a bunch of spies and kidnappers, who liked to employ dirty tactics, she preferred to double check.

Getting closer to a nearby body, she surprisingly found a smaller dagger besides a double edged shortsword, similar to a gladius. Most likely a backup weapon and utility knife, though there was a possibility that their ex-wielder could have used both of them at the same time, Sera assumed. Using her newly acquired weapons, she tried them on the exposed neck of the otherwise in bloody wet silvery metal armor clad person. The blade's sharpness surprised her at first, but as she inspected the cut, she noticed that it was probably the state of the body which let the weapon appear sharper than it actually was. A few more cuts confirmed it. The bones were broken, blood-vessels ruptured and muscles torn and presumably the organs shredded.
Well, she could only assume the later, as most of the body was still covered in armor and she didn't want to waste time removing it. Turning her head to Sarah, she also seemed to be nearly finished with her observations of the magical floor decorations.

Meanwhile, after circling around the engravings, the scientist was lost in thought about the magic circle. Or, to be more specific, the three inside of each other. It was a spell in a whole new dimension. A spell even more complex than the one she saw during the summoning, but that wasn't that surprising as the one she saw in her old world was most likely created through this one. While the circles were somewhat deteriorated through their normal use, she still could make out some basic functions. The inner two were deeply entwined while the outer one seemed to be simply an afterthought. It was still somewhat integrated into the whole spell structure, but anything inside could work basically without the outer circle.

Fighting herself out of the thoughts on the spell she didn't want to have in the middle of... wherever they currently were, Sarah noticed that her sister was done with whatever she did to the corpse and had walked back with two more bladed weapons.
The sword wielding girl was shortly contemplating whether she should give her sister the dagger, just to let her have some means for defense. It wouldn't help much, with her lack of physical prowess, and Sera could keep it as another backup weapon, however, in the end she decided to hand over the dagger.
"Here take this." Sera quickly passed over the item and continued on with their primary objective: finding the exit. Having missed the opportunity to decline the gift Sarah quickly walked after her sister, at least as quickly as all the blood on the floor allowed the two to move. "... You know i have no idea how to actually use those?"
"Whatever." Her sister dismissed her opinion. "I already have two swords..." Passing by a corpse Sera noted that it also had a dagger. Not exactly the same as the one her sister had, but probably good enough. With some quick movements she looted the weapon before continuing on. "... and a dagger. Besides, only we two know that you can't use a dagger, so it should be at least a bit intimidating."
"Fine... Though i just hope i don't have to use it."
Sarah quickly checked her mana; no changes. The ritual probably also took in all the mana from the area around it. While it was a bit weird that the mana was gone, as used mana would normally return to the world, in this case it was most likely sent to her old world to transport them.
"...And that i can recover my mana to hopefully support you with magic."

Not far from the spell circle they found the wall of the dungeon. The rocky floor and uneven rock wall made the conclusion that the dungeon appeared to be a cave easy, though with the existence of magic there was still the possibility that it was artificially created.
Moments later, still evading bloody corpses, they also reached a big door one might expect in a castle from it's size, but with it being in a similar state as the other native humans, it didn't take long to get to the other side. Sarah was pretty sure that the door was once some magic item, but ended up as another sacrifice. Intricate engravings which were now utterly destroyed made that conclusion easy. If she thought of it, she would check her log later to confirm or deny the assumption. But for the moment, looking out for traps and other surprises was more important.

The winding passage following the door was rather boring. Without the fog which was kept in their starting room by the now non-existing door, they could walk much faster, to Sarah's inconvenience. Unfortunately they had to make the most out of the time they had their buffs from the summoning and before enemies could be alerted of the situation.
From time to time they still stumbled upon smaller groups of guardians, but the blood flowing away from those warned the twins often before they could even see the next heap of used up mana sources.