I have been considering the construction of my first puzzle for some time now. Six symbols as keys for six pillars, three passages off the room.

The problem with this? I am building up. Eventually I want to reach the surface, and assuming the blue boxes z value starts at global sea level then the start of my second floor is 1.5 kilometers below ground. Once I reach the surface the entrance to my dungeon will obviously be there, so one of those three paths is going to have to lead up there.

Now the reason I even want an entrance to my dungeon despite the horrifying prospect of adventurers is fairly simple.

Because literally anyone including adventurers would know more about the world then I do. I know next to nothing about this world, and since I can't move around getting people to come to me is the next best way to find out what's going on.

I was originally thinking to have each path separate into two so there are six paths, each one having one of the six keys. The problem with this is that one of those paths would have to have some way up to the floor above, splitting it into three paths instead of two like the rest. Someone could possibly go down the wrong path, and take one of the keystones not knowing what they are for.

The sensible solution to this would probably be to have some kind of lock on the paths to the keys, but that strikes me as needlessly complicated.

Instead of that I should build a huge room around the room with the pedestals, like a big cavern, and have paths to three tunnels going through that. I can grow mushrooms in the big cave, and the big cave can have a path leading upwards to the level above rather then confusing people. Plus I can fill the big cave with traps and possibly monsters once I get some.

With that thought I begin building the cavern. I already reinforced the walls, and coming to a conclusion took enough time for some of my mana to regenerate so it's time to dig.

The cavern is going to be sizable, I could probably use it as a nexus of sorts and make each symbol have a sub-floor or something later so I want it to be sizable. With any luck this will allow me to split this floor into six much smaller dungeons each with a theme. I think the tunnel leading upwards should probably open up somewhere near the middle, so should I leave a pillar by the steam room? I could try and make some sort of vertical moving platform... like an elevator of some kind? I do need to figure out how to lower the mirror, but I'm not really sure how...

Hot water rises, and produces a sizable amount of force as it does so, the billowing steam from the chasm shot up for quite a ways, and even now a large amount rises out from the hole over a kilometer from the bottom. Condensation is forming on the walls and floor. It's not going back into the pit, if things continue like this the room might flood slightly until it.

Shit.

Quickly I give the floor and ceiling a slight incline, only enough that the water slides where I want it to. The ceiling tapers slightly up towards where the mirror is so the water slides down the smooth grey stone towards the walls, the floor tapers slightly towards the chasm. The water should drip down, feed the mushrooms, and eventually find it's way back into the chasm. Incidentally this leaves six grooves in the surface of both the ceiling and floor. Perfect.

The polished grey stone is glistening with moisture. It looks kinda slippery actually... Eh I'm sure it won't be a problem. It's strengthened with mana so it shouldn't erode. Now that that's out of the way I bet I could figure out a way to use another steam put to force something upwards, cutting off the force might let it fall back down on it's own weight. I don't want the mirror to slam back down, so I would need to find some way to reduce the force with which it moves up and down, balance it out somehow.

Balance, the thought brings to mind a strange object with a cup on either side hanging from a bar at the top... the weights counter one another somewhat, counterweighting could be used to let the steam pressure do most of the work for me. I would only need a way to force the mirror up, and then to hold it there. Locking the chains should be as easy as preventing the sliding stone block they are attached to inside their little ceiling chutes from moving. The block itself is prevented from moving currently by the chute ahead of it being too small for it to go further, steam would still leak out. The stone is far from frictionless, and grates as it slides. I probably need to find something to make it more slippery, or else it will grate loudly as it opens.

Stolen from its rightful place, this narrative is not meant to be on Amazon; report any sightings.

Of course I could just prop it up on two opposing smooth plates of metal... I swiftly replace the layers of stone on the sides and bottom with silver, I think that might be heavier, but it also might slide better.

Next I add material to the blocks, digging a trench about two thirds of the way down the block, and making a chute past that just long enough to let the block go barely past the end of the trench. The steam will flow into the chute and push the block through the trench, and then on reaching the end the steam can escape through the chain chute rather then letting the pressure keep building. Of course this will only work if I attach counterweights, made of silver bound by silver chains. These are on round rolly things my memory calls wheels and built into each corner so they pull away from the three blocks at an angle so they end up falling down chutes on either side of the three doors to the chasm room. the chutes have little rail-things made of silver keeping the counterweights on their path, wetted with condensation. Initially I put too much and the mirror pulled up with the howling shriek of metal grating on metal.I took away too much and the silver howled again as the mirror fell. I stopped it about halfway adding just a fifth less then I took and it slowed rapidly. A little more and it slows to a more acceptable rate of about a fifth of a meter per second, metal squealing as it steadily slides into place over the chasm. Steam pushes its way through the tiny circular holes around the edges of the mirror forming a circular shroud around the center of the room.

Now I make use of the three unoccupied walls of the room to hollow out and create tubes leading to each block. The steam will force the blocks away from the center, and so pull the mirror upwards. Rock seems too fragile for the pressure tubes, since the steam cracked it in the chasm, lead is too soft, and bismuth melts so... More silver. coating the circular half-meter wide chutes in silver takes a LOT of metal, even only doing it a centimeter thick. Each tube leads down to a seperate chasm, just like the first one but only a meter wide. To prevent the pressure from forcing the blocks too soon, each place for a symbol needs some way of locking in place until the right symbol is put there, then when all of them are put in place it will unlock a counter-weight to slide away the stone block holding in the steam letting it travel up the chute in a powerful blast of force. Each triangular indent's symbol should be placed on the pillar closest to the direction of the tunnel it matches. Eventually I want to make each one have a symbol on it that represents the place it was taken from in some obvious way, and... I could just forgo the idea of a seperate way down altogether. Three entrances leading up to a central nexus, somewhere a lot more practical then two kilometers underground. Each one with two paths, each one has a challenge and the reward is a symbol. getting both of the symbols used for the mirror along a pair of paths opens a special reward of some kind, but that would use up the symbol for that run. I would need to find some way to make the symbols one-use...

Bismuth. It melts, and getting heat is not really a problem for me. Higher up it could be difficult, but I could pour molten metal into a mold, and the metal melts when put into the right slot, draining off for me to re-absorb and then put back for re-use. I can create magma, so heating up a furnace should not be much of a problem, plus there is an absurd amount of fire mana around here from the magma sea. The keys will probably be fairly heavy, considering each one is twice the size of a person's hand and made of metal, and the keys will also be destroyed if exposed to too much heat, but that seems like a useful challenge.

The Mirror room is now a temple, sitting in the center of a vast cavern, nearly three hundred meters tall, and seven hundred across with massive stalactites. I dig out the floor a good three hundred meters, sloping down with numerous thin fissures and even silver pipes leading off to chasms. I force fire mana into the surrounding stones, then something unexpected happens-

A small diamond in one of the rocks turns red, and starts to shine with heat.

New Material:

  Primal Fire mana crystal. Burning with a brilliant internal flame these shards of gemstone are imbued with immense quantities of fire mana and can only be found in the hottest places far underground. Costs 50mp a cubic cm.

I can think of more then a few uses for this.