The next thing to fill was my third room. I had a room testing strength, so this room I wanted to test speed and reactions. As I looked at my options, I figured any of the ones I'd gotten for free might work. Actually, I wasn’t sure about the snake. As it was the only one I hadn't made one of, I decided to use them for this room, assuming they fit my needs. I had sort of picked the lizard to be my boss, as it was the first mob I'd ever made, and Ari obviously loved playing with it.

That left me with the decision of what material to use. I was tempted to use soil, as that had proved fairly quick, but that seemed pretty weak. I started looking through the plant options, looking at which ones had enough earth essence to give me the discount. Turns out, most of them did. "Ari, why do so many of the plant materials give me the discount?"

Ari smiled, still watching the new sprout in my core room. It hadn't done anything, but I wasn't surprised she didn't want to let it out of her sight. "They are a combination of earth, water, and life essences. The discount is pretty forgiving, anything that can reasonably be considered related to earth essence will probably give you the discount."

That was good news. I had assumed I'd be limited to things that were almost entirely related to dirt and rocks. I was glad to know I would be able to have a bit more variety in my dungeon. I didn't have too many different plant types, but as I looked through them, I found one that made me grin evilly. Or, well, I would've if I'd had a face to do so with. I tried to make my lizard grin evilly for me, but it just looked like it opened its mouth a little bit. Problem was, the plant I wanted to use I only had part of the plant. I wanted the whole thing if my idea was to work. "Hey Ari? If I have a seed for a plant, is there any way to get the other parts?"

Ari nodded. "Yeah. Just like your essence helped this mana tree sprout quicker, you can do pretty much the same thing with a normal plant too. The difference is that the mana tree only needed essence to survive, you'll have to make sure the seed you want to grow has nutrient-rich soil and water, but your essence can replace the sunlight and time needed for plants to grow normally. Some plants this works better than others, and just about any plant with magical uses either needs to grow naturally, or uses so much essence to speed up the growth process that it isn't worth it, but for most basic plants it will work just fine."

"Sweet! Thanks!" I had patterns for soil and water, so I made a pile of soil in the third room, got it nice and moist, and created a seed on top. Then I realized that the mana tree seed had taken the essence on its own. I was about to ask Ari how to feed essence to the seed, but decided to just try it. Most of being a dungeon core seemed fairly intuitive anyway. I tried to remember how it felt when the mana tree seed had pulled the essence from me. I tried to push a bit of essence to the seed I'd created, and suddenly I saw a tiny dot of light float out of my core and down the tunnel towards the room with the seed. It looked a good bit brighter than before, and I guessed that it had something to do with the mana sprout's benefits.

The dot of light reached the seed and sank down inside. It was just like the accelerated growth of the mana tree seed right at first. The seed quickly broke open and roots shot down into the soil. I could tell they were sucking up the water quickly, so I hurried and added more water to keep the soil damp. The plant sent feelers out over the soil, growing large leaves. The feelers buried themselves in the ground and started sending out more feelers. Soon there was a small patch of thick green leaves. There were also some large red flowers and a few were ripening into seed pods. It wasn't a tall plant, it actually reminded me of how strawberry plants grew in my Mom's garden back on earth. Back on my earth? I wasn't sure why this world also just happened to be called earth, but it made me confuse myself sometimes.

Language problems aside, I now had all of the different things from the plant. I smiled evilly again as I read part of the description I got about the plant. "The leaves excrete an oil that causes mild irritation in the skin of most creatures." I'd found poison ivy. The name it had here was apparently "flaming bloomer". I imagined it had something to do with the bright red flowers and the burning itch I remembered from the one time I got on the wrong side of a patch of poison ivy.

I selected the leaves of the plant as the material for my snake, and hoped it would be what I wanted. It formed in the middle of the room. Move quickly around the room. I didn't want to tell it to run around the room, but I wanted to see how fast it was. It wasn't as quick as the lizard or mice, but for a creature with no legs I thought it was pretty good. I had it go into the patch of flaming bloomer I'd grown. It became practically invisible. I could see the essence animating the snake, but otherwise I knew I would probably lose track of it.

I created a block of clay in the room. At first I was going to do wood like for the badger, but realized the snake was probably not as strong. Attack the clay. The snake acted differently than the badger had. Instead of rushing and attacking it in a frenzy, the snake slithered slowly towards the block. Then it coiled up and … struck! Twice, three times it struck at the clay. Stop. The snake froze. I found it interesting that the mobs copied the habits of the animals they were copies of. The badger used no subtlety at all, while the snake acted like an ambush predator. That was good, it meant the mobs wouldn't need me to spell everything out for them. Although as I watched the snake just sitting there a few feet away from cover, waiting for instructions, I realized I would probably have to give a decent amount of instructions since they had no intelligence whatsoever. "Ari, I just made a snake mob, and it seemed to understand that it should strike from hiding but doesn't seem to understand that once it's done attacking it should hide again. How intelligent are my mobs?"

Ari tilted her hand from side to side in a so-so motion. She was now sitting on my core, although she was still watching the sprout. I had a feeling she wasn't going to leave that room for a while. "First, none of your mobs are actually 'intelligent' per se. They don't think, they don't feel, and they can't really make decisions. Still, for reasons no one knows, mobs do tend to get better at fighting as your dungeon gets stronger. Also, stronger mobs will employ more strategy than weaker ones. And if you put a mob in front of two tunnels and say 'go down a tunnel' the mob will obviously have to pick one. Some people say that the mobs actually do have a method of learning that somehow stays with them even as they are killed and rebuilt by you, but it's never been proven or even really had any convincing evidence. And there's never been a single instance of a mob not obeying every command of the dungeon to the best of its ability. With that said, eventually your mobs will get the basics of fighting strategy down, but at the start it's mostly up to you."

That made me curious. I'd have to see what I could discover about how my mobs learned. For now, though, I looked at the block of clay. There were six small holes in the block where the snake's fangs had penetrated. It didn't look like this mob was going to be very dangerous. I looked closer at the block of clay as something caught my attention. There was a small drop of liquid in each hole. I looked closely at the fangs of the snake. They were hollow! I looked at the liquid in the clay. It was the same oil produced by the flaming bloomer. I wasn't sure what effect it would have inside of you, but these snakes would at the very least make you very uncomfortable.

Still, the room wasn't very deadly. If I wanted essence, I needed deaths. And Ari had explained that an adventurer who didn't die at least occasionally was considered a coward, so I needed to make sure there was a decent chance of death, not just rashes. I thought about how to make the room more dangerous. Then I had a great idea. The snakes were made out of leaves. Which meant they were extremely light. I remembered a classic trap from movies or books I had watched or read: the pit trap. As my plan for the room started to solidify, I started expanding my essence below the room's floor. I could definitely tell a difference in how far I could expand my influence with the same amount of essence now that I had the benefits from the tree. Soon I had expanded my influence a good 50 feet below the floor. Oddly enough,in order to go so deep I had to dig tubes straight down so the essence didn't have to push through too much rock. Although I noticed that the brighter essence could push further into the rock without it causing problems and becoming more expensive. This mana seed was already proving very valuable.

Once my influence was sufficiently deep, I dug some pits. The first one was right in front of the entrance and was designed as a warning. It was only about four feet deep, so nobody should get badly injured by the fall, and Ari had warned me that the adventurers would always have a healer, so anything non-lethal was temporary, and not even that dangerous. I made a half dozen other holes scattered around the room, which I also expanded slightly. The other holes were deeper, culminating with one close to the exit that was over forty feet deep and had sharp stone spikes at the bottom. That one was the only one with spikes, and it would definitely be lethal. I then added thin layers of stone above the pits, thick enough to support the weight of the snakes, but not a lot more. I then sprinkled some soil everywhere and scattered flaming bloomer seeds everywhere. A bit of water and a bit of essence later and the room was carpeted with a thick layer of green, with random big red flowers.

I made ten of the snakes, since they weren't very dangerous. Their job wasn't to harm the adventurers, their job was to irritate them so the adventurers would chase after them. Then the snakes would go over a pit and the adventurers would have only a split second to react when they felt the ground giving way.

Now it was time for my final room. The boss room. I realized I didn't even know how to make a stronger monster. Ari had said my boss would be the strongest enemy in the dungeon, but I didn't know how to do that. "Hey Ari? How do I make a boss monster, anyway?"

Ari was still a bit distracted by the new occupant of my core room, but still responded. "Sometimes you'll have a powerful evolution that would work for a boss. But if not, you can force a mob to evolve by pushing extra essence into it. Basically you shove it full of far more essence than it can handle and it evolves to a more powerful mob, using up that extra essence."

Sounded pretty simple. Also, it sounded like I needed a lot of essence when I did it, so I looked around my dungeon a bit as I waited for my essence to regenerate. There sure was a lot of waiting as a dungeon core. I looked at my dungeon menu.

Alex Johnson

Earth Core - G5

Essence - 147/500

Core generation - 10/hour (3/hour to bond)

Dungeon generation - 40 per hour

Dungeon actions:

Increase influence

Absorb matter

Create item

Create mob

I decided to put 300 essence into my first attempt at a boss mob. As I waited for a couple of hours for my essence to fill, I started giving ground rules for my mobs. First thing was that if my core or Ari were ever in danger, those took preference over any other goals. Second was to never attack Ari or my core. After that I started giving more detailed instructions to the badgers and snakes. The mice in the first room I told to just charge directly at any intruders who entered the room, but to otherwise act like normal mice. I preferred them scurrying around to standing there like statues. The badgers I told to charge directly at anyone intruding in the room, but also gave some secondary commands designed to help them make use of the stalactites in the room. I told them to always try to keep a stalactite between them and any ranged attackers. I wasn't sure if they understood what I meant by ranged attackers, but hopefully it would help.

Reading on Amazon or a pirate site? This novel is from Royal Road. Support the author by reading it there.

The snakes were a little more complicated. The badgers I planned on using a very simple strategy of "try to run them over", but the snakes needed to be sneakier. I told them to stay in the leaves as much as possible, and when they attacked an adventurer they were to strike once and then slither away as fast as they could. They were to try to go over a pit if they could, and keep slithering until either they were killed or they could hide again to go do another surprise attack. Hopefully they would manage something like what I was envisioning.

After a few more hours of doing little stuff to spend the time my essence was at full 500. I had decided I didn't ever want to be completely out of essence, just in case. I looked at my lizard. My first mob. Time to boost him and see what happened. I told it to stand in the middle of the boss room, because I wasn't sure what would happen when it evolved. Then I tried to do the same thing as I'd done with the seeds, but instead of pushing a little bit of essence, I pushed as much as I could. A thick white stream glowed brightly as it flowed from my core, down the tunnel, and into the lizard. At first the lizard just stood there shaking. Then it fell apart. Not knowing what else to do, and not wanting a useless pile of dirt as my first boss, I kept pushing more essence into it. The dirt turned into black smoke. I kept pushing essence into the smoke until I couldn't anymore. I looked at my menu. Completely out. The smoke thickened, then solidified into a black ball. I wasn't sure what to think. Move around. Nothing. Float? Nothing. Do something! Not even a twitch. My first boss was a immobile black rock.

Suddenly there was a loud *crack!* sound. I looked at the ball in hope. There was a crack on one side! As I watched, another formed. And another! The ball wasn't the boss, it was like an egg that contained my boss! The cracks spread, and pretty soon the side of the egg broke open, revealing my new boss. I wasn't disappointed any more! "Ari! Come look at my new boss mob!"

That snapped her attention off of the sprout. "Your new …" her expression fell. "Oh no."

That wasn't the reaction I expected at all. "What do you mean 'oh no'?"

Ari shook her head as she flew off of my core and into the tunnel to the boss room. "You can push essence into a mob to make it evolve, but you'll usually only get a good evolution once per tier. You shouldn't have made your boss until right before you opened to the world, so you could put as much essence into the evolution as possible."

My spirits fell. I'd assumed I could try again if I messed this one up. To hear that I probably only got one shot at this per tier was … not good. "Well, I pushed a full 500 essence into it." I said hopefully.

Ari smiled sadly. "Hopefully it isn't too bad." She made it to the boss room and stopped in shock. Where before the lizard had been only about a foot long, now it measured probably 10 feet or more from head to tail. Before it was made from soil with small pieces of stone mixed in, now it was made completely of a black stone. It kind of reminded me of obsidian, but without the shine. Before, the mouth of the lizard was small with sharp pointy teeth. Now, it had a large jaw like an alligator with far larger teeth. The claws, instead of being small and straight, were large and hooked like a bird of prey's talons. And where before the tail had been just a cord of dirt, now it ended in a sharp barbed needle. It looked almost like a narrow spearhead or arrowhead.

Ari hovered there, staring at the mob for a bit, before she realized what had happened. "The sprout! You said it would make your essence better at creating mobs! And it had the benefit of better evolutions! It's probably a good thing you didn't add any additional essence, this is an unusually strong looking boss for a new dungeon. Have you seen it fight yet?"

I sent a mental shake of my head and made a large block of wood in the middle of the room. I had Ari fly to the top of the room, then got ready to see my new boss mob in action. Attack that wood!

The mob sprinted toward the wood block. As it arrived it jumped up on its back legs for a second. It obviously couldn't run that way for long, but it meant when it ran into the wood its front two legs were in perfect position to start gouging large slices into the wood. That wasn't all, either. It slashed at the block with its tail and chewed on it, leaving dozens of deep gouges within a few seconds. It kept at it until I told it to stop. I was impressed.

Ari was too. "Wow! That thing has some impressive damage output to a stationary target! Tanks are going to have some problems facing that!"

She had explained the classes of adventurers to me before, so I understood what she meant.

"Give it something to fight!" Ari was just as excited as I was. I was glad this boss wasn't pathetic like it might have been. I summoned one of the mice I'd used in the first room. Fight each other. The two charged at each other. It was over pretty much instantly. Snap, crunch, no more mouse. I made a couple of the badgers from the second room, a half dozen snakes, and a dozen mice and lizards. Time to see what this boss could really do. Fight! This time the boss was serious. A cloud of darkness swept from the boss, and the other mobs froze as the boss seemed to sink into the darkness. I could still see it due to the essence infused into it, but I could tell that to normal eyes there were no signs of what was happening.

I saw the boss mob snap its tail like a whip! Suddenly one of the badgers collapsed, and I saw the tail spike from the boss lodged in its head! The mobs all ran towards the spot the spike had come from, but the boss had already moved. It snapped its jaws shut on one of the snakes as it slithered past, cutting it into pieces. The tail, which I could see was slowly regrowing the spike, smashed into one of the mice, absolutely obliterating it. It kept going like this for a couple of minutes. The boss would pop out of the shadows, kill a mob with a single hit, then fade away before the rest could get there. It didn't attack the badgers, as it couldn't easily kill them in a single hit, until it regrew its tail spike. Then another badger was down. I didn't think the other mobs were ever going to be able to stop it, but eventually the cloud of darkness disappeared. The black boss on the white marble of the boss room stood out like a sore thumb, and immediately the other mobs were after it. It still did all right, but it turned out the stone it was made from was also fragile like obsidian. A good hit from the badgers would make a large crack, and while the snakes, mice, and lizards couldn't do much damage initially, once there were cracks they could widen them slightly. In the end the boss managed to take down another badger by using the same jumping motion and slicing it apart with its front legs, but this let the final badger get a solid hit in on its back, finishing the fight.

I sat in awed silence for a moment. "Wow."

Ari was clearly impressed as well. "I take back my earlier statement, and change it to 'It's definitely a good thing you didn't add any extra essence.' In fact, you may have to make a new boss anyway! This is probably way too strong for a beginner dungeon, especially that dark cloud skill. You managed to find a rare unknown evolution."

I wasn't sure what that meant. "An unknown evolution?"

Ari smiled. "Many evolutions are pretty common, and have standard names. A firebird can evolve into a phoenix. A salamander can evolve into a dragon. But occasionally, a dungeon discovers an evolution that's either never happened before or is rare enough that the resulting creature isn't well known and named. Finding these rare evolutions is really good for a dungeon. An evolution is already less expensive than it should be for how powerful it is. A previously unknown evolution adds an additional 50% discount on top of that!"

That was incredible! I'd been worried I wouldn't be able to create this boss mob again, since it seemed far more powerful than anything I'd been even close to creating thus far, but a 50% discount would definitely make up for that. "Ari, how has no one found this evolution before? Is it just a random chance?"

Ari shook her head. "Mobs evolve to follow what they've experienced. I think I can explain a lot of the changes of this mob during this evolution. It's been in a large room this whole time, so it grew larger to fit the large room. Mobs in tight spaces tend to shrink when evolving. It's been in a room formed entirely from rock, plus rock is just a stronger material. The only creature it has had any interaction with was me, a flying creature, so it developed a ranged attack. Finally, it has spent its whole life in the dark, so it developed abilities that benefit from darkness."

All of those made sense except the last one. "What do you mean it's been in the dark? The room's made of white marble, and is lit quite brightly." There weren't even any shadows.

Ari smiled. "To you and me it's pretty well lit, because we can see using your influence. But what have you placed to actually make it brighter in here?"

I realized there was nothing. I had even made the chandelier, but hadn't added any light sources to it! "But then how do the mobs see at all? They could chase the boss once its dark cloud dissipated!"

Ari smiled again. "Your influence does shed a small amount of light. But it isn't very much. It's pretty much black in here. Probably the only reason the other mobs could see the boss was the white marble."

That did make a good bit of sense. It wouldn't take much light to see the black boss against the white stone. Still, that was just one more thing I needed to do before I could open my dungeon to the world. I assumed the adventurers wouldn't appreciate having to fight in the dark. Besides, then they wouldn't be able to see my glorious artwork in the boss's room. Although I would probably need to change the color scheme to match the boss a little better.

Ari smiled. "Now there's only one thing left to do with your new boss!"

"Really? What?"

Ari grinned. "Naming it! When you make a new evolution, you get to name the resulting creature. This is the name the adventurers will see when they examine the boss!"

Really? That was interesting. Most of my mobs had been given automatic names, and frankly, they were pretty boring. "Soil lizard", "Wooden badger", "leafy serpent", and such. I decided to give my boss a much more impressive name. Hmmmm. What to call you? I thought about the display it had just given. That thing would probably be pretty terrifying to fight, especially during the skill with the dark cloud. I smiled. I had the perfect name. "Ari, how do I name it once I've chosen a name?"

Ari smiled. "Go into the menu to create mobs. There should be an area in the spot where you usually chose 'golem' called 'evolutions' or something like that. Then there should be an 'unknown evolutions' area. Once you're there you should see something like 'unknown soil lizard evolution' or something along those lines. Just focus on changing it to a new name and it'll do it!"

I followed her directions. It was called exactly what she'd predicted. I did not want the adventurers to see "unknown soil lizard evolution" when they faced my boss. "I want to call it 'Night Terror!' We can just call it Night, for short."

The name obligingly changed to "Night Terror" in my menu. This was so cool! I couldn't wait to see the first group of adventurers face Night.

Ari was still up at the ceiling of the room. "Now we have a problem."

Huh? I thought everything was going pretty well! "What's the problem?"

Ari shook her head. "That boss is far too strong for a brand new dungeon. You need to find a different boss."

That was a problem. I wanted Night to be the boss, and Ari had said if I tried again I would probably get a garbage evolution. Besides. I really wanted that 50% discount! "Ari, what if I have it act differently based on the strengths of the adventurers? A brand new adventurer group Night would just charge straight in, like he did against the wood block. Once the adventurers are a bit stronger he'll fight smarter, trying to sneak around and attack the weaker members of the team, like mages and healers, first. And only if the group is unusually strong does Night use his cloud skill and his ability to sink into the darkness?" I had noticed that Night's hiding in the darkness wasn't purely due to the dark stone he was fashioned from, it was also a bit magical.

Ari thought about it for a second. "The adventurers would be getting more essence than they deserved, but that's fine for you, because you have the 50% discount. And it wouldn't be too strong for new adventurers, while still posing a challenge for stronger ones. I like it!"

I smiled. I had just made my first boss mob. Now I couldn't wait to open up to the world. First, though, I had to get my dungeon completely ready. Now, how to make lights?