What Ben means by Serena's gift is the green lacrima ball that he placed on the altar. That lacrima ball is Cavern Dragon Lacrima he got after killing Serena. It contains strong Earth-type Magic, so it is really suitable to maintain this skyscraper.
He got 2 Earth types of Dragon Lacrimas from Serena's 8 Dragon Lacrimas. They are the Cavern Dragon and Diamond Dragon Lacrimas. The Diamond Dragon Lacrima will make this building tougher, but it will need more magic power to maintain, so Ben uses the Cavern Dragon Lacrima because it's strong enough already.
The Burj Khalifa's imitation stops glowing after 10 minutes. Ben touches the Cavern Dragon Lacrima to check the result. He can see every corner of the building through this lacrima to check it, and he is satisfied with the result.
Monsters have filled the building from the 1st to the 100th floor. The monsters are stronger the higher the floors are. So it's like those dungeons in RPG games where each floor number represent its level with level 100 as the most difficult.
The higher the floor, the stronger the monsters, but their number also reduces. There are 100 monsters on the 1st floor and there is just 1 monster on the 100th floor. That 1 monster is the strongest here and it can wipe out the monsters in this entire dungeon by itself.
Although this dungeon is powered by a Dragon Lacrima, the monsters here are normal, except for the strongest monster. That monster is a Dragonoid, a humanoid dragon that looks like a human with Earth Dragon traits.
So it's like a Dragon Slayer in Dragon Force, but it's just half as strong as normal Dragons. Still, it is a very powerful monster and it's very difficult to defeat because it is a kind of Dragon. Even Dragon Slayers will have a hard time fighting it.
Ben programmed the Dragonoid to have great battle abilities that can maximize its power. Its battle abilities are based on Ben, so it's a kind of his clone with different magic. So those who can reach level 100 will face the weaker version of Ben with Earth Dragon Slayer Magic.
But that isn't even the worst thing that will trouble the challengers. This dungeon is made for Fairy Tail members, so Ben made it to be very suitable for them. He installed everyone's data into the monsters' minds, so all these monsters will fight differently based on who their opponents are.
Worse, all these monsters are connected, so they can move strategically. Then even worse, the monsters on the next floors will also get information on how the challengers fight on the lower floors. So the difficulty will increase a lot by each level that it will be impossible to clear for most Mages.
Even when they retreat and challenge the same floor again, it will be more difficult than their previous attempt because the monsters will remember their abilities even after they died and respawned. Many people will be frustrated, but they will grow even more if they can pass that challenge.
He won't tell it to anyone though because it will be better if they don't know what awaits them. Ben deliberately made the dungeon like this to maximize his guildmates' growth. A normal-type dungeon won't be enough, especially for those S-Classes or the ones with S-Class potentials.
Anyway, the dungeon has been built and the monsters are ready. So Ben comes out to tell his guildmates who wait outside. There are many monsters on the 1st floor when he comes out of the control room.
"Cuties!" shouts Bella excitedly when she sees the monsters on the 1st floor.
The monsters on the 1st floor are really cute, after all. They look like rabbits with round bodies, short legs, and cute faces. But their cuteness is a trap that will make challengers who are weak against cuteness.
When they get distracted, the round rabbits will attack them. These round rabbits are actually strong enough to knock out even adult Mages, after all. They are fast, strong, and have a great number.
But, these round rabbits are very docile to Ben and they all just act cutely in front of him. He is their creator and owner, after all, and they know it very well. No monster here will attack Ben and he won't attack them anyway.
Even if he is ruthless sometimes, he just doesn't have the heart to kill what he made himself. Even thinking of these cute guys getting killed makes his heart aches. But they won't truly die in this dungeon, they will simply resurrect again. They will truly die when this dungeon disappears.
"Take care of this place for me, alright? I'll come every once in a while, so don't be lazy," says Ben while walking away.
"Kyu! Kyu!" the round rabbits salute to him like soldiers as he leaves the dungeon.
Ben comes out of the skyscraper dungeon and sees everyone is still stunned by the very tall building. They never see a building with such a height and design, after all. So they are very amazed and can't take their eyes off it.
They only wake up from their astonishment after Ben claps very hard. Now their attention shifts to Ben who made that building. They ask so many questions at once that Bella is getting dizzy hearing them, so she wears a headphone to block the noise, but Ben just stands there without saying anything.
Only after they stop talking in half an hour that Ben says something. "You guys sure have a lot of questions, but I can't answer them all, so I will just explain a few things. First thing first, this building's name is Dragoram Tower."
"I'm sure all of you have known that this is a training facility for Fairy Tail Mages. But it will surely attract tourists who just want to see this or even Mages who want to try their luck. I haven't had any intention to let foreign Mages enter it, but I can't prevent people from coming to see it from outside. So you guys need to be ready for that," says Ben before walking away.
"Um, that's it?" asks a man.
"For now, yeah. There are too many things to explain, so it will be tiring. I will write a few things about it and publish it in our newspaper later so you can read them yourselves," says Ben before signaling his guildmates to follow him back to the Guild building, leaving the stunned public.
In the Guild building, Ben starts explaining the basic things about Dragoram Dungeon. It is basically just a dungeon that goes up instead of down. They won't get any reward item after defeating the monsters, but they will get valuable experience, it's a training facility, after all.
They ask quite a lot of things, but one of the most important things is that they won't die in the dungeon. The dungeon will teleport them out of it instantly when their health becomes too low, so they shouldn't die.
Ben limits the number of challengers to 5 or it will be ineffective if too many people challenge it at once. They also need to enter it in turn for the monsters to respawn first. The monsters will respawn when the previous challengers enter the next floors or get kicked out.
Anyway, all the rules in the dungeon are ensuring their safety while they train to get stronger. The monsters on the upper floors are also strong enough even for Gildarts and the building can repair itself, so it won't get destroyed completely.
When Ben is explaining, he suddenly gets a call from Mira. She is telling him that she has wiped out Mikage Branch by herself. Even Ben is surprised by it, "Damn, that's fast."
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You can read up to 35+35 chapters ahead of my fanfics and more pictures on my Pa_treon page if you are interested.
Voting for this book is highly appreciate. Cover image is the MC, artist's ig: @fatmaqn_
I've uploaded:
1. Chapter 407 of Fairy Tail: Sun Eater
2. Chapter 418 of Transcended as Lord Buggy
3. Pictures of both stories (ex: bounty poster & magazine cover) by fatmaqn_
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