Monster Integration Chapter 15 Cave In

I was just about to dial it back my mana circulation to the sixth move of Supreme Combat Exercise because this pain nearly making me nearly black out but I didn't get the chance to do that because another hole open near me and monster started to swarm out.
"fuck…" I cursed seeing a group of the monster's coming toward our direction, soon it spits and five lv. 3 monsters come to my way. "Ahhh save me save me!" I heard when I looked to see a man being eaten alive by Red nail Rat monsters.
"Slinc slice…" I cut to kill another monster leaving four behind, these new monster's are quite smart, they attack in coordination, it makes really hard to kill them.
"Clang clang clang slice" another monster got heavily injured by me, I only able to slice 1/3 of its neck, a fountain of blood could seem to ooze from its neck, it will soon die to leave behind three monster's for me to kill.
Having killed two monsters, I felt a little relaxed, it gave a chance to catch a breath. fighting monster against life and death helping me endure the pain of ninth move of the Exercise, the pain is still immense but at least l got out of the fear of blacking out amidst the fight.
"Slice" "yeah!" I shouted as I killed two monsters in one move, it was a little risky move as one monster jumped to attack my head and other two were attacking my legs.
To kill two monsters on the ground, I had to sidestep at last second when Red Nail Rat's nail was very close and perform very large horizontal slash close to ground cutting both monster's in half.
I didn't get unscathed out of it, my shoulder got injured by the rat who attacking me from jumping, I move backward and stab last remaining monster in it head killing him on the spot.
I didn't have the luxury to entertain rest as I quickly remove the bandits and quickly pasted them all over my body, I have to thank my mother if I am able to survive this for packing so many band-aids.
These band-aids are especially for monster's band-aids but can also be used on a human, I just have to place them near the injury and they automatically spread on injury closing the wounds.
These band-aids are called Micro bandaids made with nanotechnology, they are fingernail size but they cover the wound size of adult fist easily.
"Chu.." Ashlyn is eating the hearts of the monster that I killed, "Ashlyn eat quickly," I said to her because I know new monsters will soon come.
It looked like a long time fighting but barely three hours passed since I started fighting and it will take near day at least for reinforcements to come, the situation looked bleak but still, all people are fighting with all their heart.
Ashyn started cooking and eating the hearts of the, I really wonder sometimes how she able digest all in her palm-sized body, the five hearts she just ate right now is size small child's fists.
I have to do something about the Mana, I am running out, I only have about 20% left. I don't have mana potions like Jim, the only option is to eat monster's meat which is enriched with mana but for human digesting they take time.
I was about to pick out a monster heart from their bodies to eat when a group of three red nail rat attacked me, I barely dodge their attacks, "clang clang" as my sword and their nails touched sparks flew out.
I took back the silver fire which was coating my sword to save mana but it decreases offense a little, I kept circulating the nine the move of the exercise and didn't dare to circulate the tenth move fearing to blackout.
'Beep' a notification lighten on my Holowatch but I am not in the mood to read as I fighting. "fuck me!" cursed Jim, this was the first time I heard him cursing when I looked to find him reading something on his Holowatch while fighting monster's.
"What is it?" I asked, to make Jim cursed this must be something important, "Mr. Black informed that many low-level monsters will come from underground soon and he won't able help us as he and other lieutenant stage powerhouses are holding back Lieutenant level monsters" Jim replied.
My heart skipped hearing that new, till now many holes were open and monster come out but Mr. Black didn't want anyone but this time he warned, this would mean only one thing a large amount of monster will come soon, that means we probably have maximum half an hour before big lot monster's come.
Without thinking consequence of blacking out, I circulated mana in directions of the 10nt move, "ahhhhh" I screamed in pain.
Even if I blackout and fell unconscious death await and if I didn't try my all, the death is awaiting me similarly, of the two choices I would prefer dying while fighting.
I circulated eleventh and twelveth move consecutively without caring for consequences, the wins all over my body popped out as they will burst any second.
"Slice sloc slice.." in within second I was able to kill all them but my mana also reaches extremely low, only 10% is remaining in central storage.
Without resting, I dig out the heart of the monster and cooked it for ten seconds with silver fire and ate it in one bite.
I ate seven hearts till I can't eat anymore, the tastes of the hearts are not as disgusting as I thought it would be, in fact, they are quite tasty.
I just hope they will be quick digested but to my surprise, I digested them within minutes I ate them. I didn't understand at first but then remembered.
The information I read about the Supreme Combat Exercise, it said that circulating Exercise will help to digest faster, the more moves I circulate the faster my digestion would become but I didn't have put much load on that.
Twenty minutes passed since I heard the notification, the monsters will come soon.
As I killing any stray monster which comes in my way, I notice my big mistake when I didn't feel any new mana which I should get from eating monster meat.
I looked inside my Mana World, "fuck fuck fuck I am a fucking idiot." I cursed myself when I forget the most important drawback of my Refinement Engine.
That I will not able to any other mana except which stored in Central storage of Refinement Engine, the mana my body absorb and mana I get from the monster meat will turn it mana cloud around the Refinement engine.
To use that mana I have to absorb it into the engine to refine and store it into refinement engine. The large mana cloud already had surrounded the refinement engine, it was much time bigger than first mana cloud which I had absorbed into refinement engine.
The mana I got from eating monster meat is faint in color, obviously purer that the mana my body absorbed from the surrounding, to know the purity of mana I have to refine it first.
"Ashlyn comes," I said and Ashlyn come inside me, I started to operate Refinement Engine to refine mana cloud while performing the twelfth move of mana calculation engine.
It put so much strain on my mind that three blood veins of my head cracked apart and blood started to trickle from it.
I was in no mood to consider that because I could feel little vibration under my feet and I know when they will reach the surface, large number of them will pour in.
"Bang." loud bang heard from the center of the battlefield as the ground started to cave in, many people in that fell into a big hole, there is no need to think about there outcome.
"Tatatatatata" sound could be heard from the ground and soon wave after wave of black and red started to come out of the hole. I gripped my sword strongly as I waited for monsters to come.