With a swift motion, the hell-hound lunged at Damian, jaws wide open, ready to sink its teeth into his soft flesh. But Damian reacted with lightning speed, sidestepping the attack and slashing at the hell-hound's hind leg. His hours of sword practice kicks in, and proves to be invaluable.
The hell-hound howls in pain, momentarily stunned by the unexpected counterattack. This gives Damian a precious moment to which he uses for a clean sword strike to the monster's heart.
As Damian catches his breath, adrenaline coursing through his veins, he stands proud before his fallen adversary.
He was outside the lab with a short sword that was very conveniently placed right next to the door.
So now he was in an incredibly tense situation, where he was trying to survive and build. He didn't come out without a plan, just as the 30 minutes timer for re-entering the lab appeared on the closed lab door, Damian put out the parchments on the lab wall in large quantity all with the runes of air.
It was the edited version though, and the intensity was set to moderately high, the best part about the rune of air was that it did not produce air out of magical ink but instead used the air of the atmosphere and propelled it through a ring with force which conveniently could be adjusted just as fire rune ring size, which created an effect of flowing air - just like a modern world fan. Also It used considerably less mana than fire or water runes since it did not really generate anything.
The reason why Damian did this was to buy some amount of time to build his temporary base outside the lab door. The airflow which was so fast that even opening the eyes for a long period was hard near the lab, so the hell-hounds avoided the place near the lab like a plague. But still some brave or dumb ones came to fight him despite the odds. Just like the one he just defeated.
Damian was trying to build a bunker before the air runes ran out of mana, which according to his calculations should be around 35-40 minutes. He was using the earth rune to build a wall in a circular shape with the lab door as center. With the new mana ink even the basic earth rune would produce an uneven earth wall of 5 meters tall and meter thick, however because of their unevenness he had to stick them really close to each other and it took a lot of time.
After building the circular earth wall he also built a moat around the wall to give it an extra layer of protection. Of course he left a place from where he could go outside, and also a place for sniping from inside his walls. In order to create the moat he had to use a very powerful attraction and repulsion runes. Even with the new powerful ink the attraction rune could only dig a meter long uneven shape of land with highest setting that lasted only two seconds, with which he painstakingly dug bit by bit, and threw it all out of the way with repulsion runes which had the same cost of working. Then he filled it with more than 50 water runes, still only knee high water was filled in the moat which was enough to drown Hell-hounds if any actually fell in it.
Damian had used more than a quarter of his mana ink stock, and many parchments, papers on preparing all this with runes, but it was all going to be worth it. With all this prepared, he just needed to use fire runes to raise temperature around the lab which will attract the Hell-hounds, then he will snipe them and kill them. And They won't even be able to rush at him because of the moat filled with water.
It took the rest of the day till late evening when Damian was finally finished with all his defensive preparations. In doing so he had killed more than 8 Hell-hounds who just couldn't leave him alone. He entered the lab and in a corner where the facility for washing was available, he took a shower and finally slept in the other corner of the lab where a bed was conveniently available just like a stockpile of month worth of food.
The next day he activated 10 fire runes together and raised the temperature of air around the 5-meter tall walls. And as expected the monster swarmed towards the heat source. Damian prepared his water rune scrolls and aimed at the nearest Hell-hound.
A high-pressure drop of water pierced the skin of a monster and left a bleeding wound behind. Even at the highest settings, of course it was not enough to kill the monster in one shot but the accumulated wounds will end up killing the monster with extreme bleeding. This was the best weapon Damian had since there was no bow and arrow inside the lab, and even if he had it, he didn't know Archery at all. It was a major strain on his already spent mana ink, plus it took the water rune a second or two after saying 'Activate' to work, but this was the only long range attack he had currently, and he had a pretty good aim.
Damian would snipe and kill the monsters as long as the fire runes worked and the atmosphere stayed hot around the walls, once it goes down after running out of mana and temperature cooling down naturally, Damian would remove all the monster corpses while staying vigilant. More than once he had to kill few remaining stubborn bastards who would not leave even after temperature cooled down, then the heating and sniping process would repeat.
And so he continued with this process all day, everyday, in this one, lonesome corner of space.
After 20 days Damian killed the last remaining Hell-hounds who were attracted by the fire rune that now cooled down. In these 20 days he spent almost all his time, killing this creatures and now finally he ran out of parchments and paper. His mana ink was also too low to draw the runes on land, because it was not an efficient material to draw upon. It wasted almost a third of the mana and only worked with 1/4th efficiency.
He returned to his lab where on top of the entrance a bright 186 was blinking with red neon light.
"Hell! What now? I am already at C rank but just to be safe I need to reach B if I can."
He knew that the greater his ranking, the better the rewards were, since all kinds of stories about brave heroes beating overwhelming odds to receive amazing skills were written all around in the Baron's Library.
Damian took a shower and slept for a while, after waking up and finally deciding to brave the challenge he took his short sword, and the last 12 parchment scrolls with a small test-tube of ink with cap on it and stepped out of the lab.
It was time for hunting.