I am planning a one dwarf megaproject. The entire megaproject will be one dwarf's lifelong fey mood. My plan is to have one superdwarf do all construction, pumping, mining, engraving, furniture creation and placement, etc. by himself. He'll work on it singlemindedly and without help. He's going to develop a lot of legendary skills in the process, so I figured I should finish the job. I'll be borrowing heavily from the experiences shared in
this thread once the tower is finished. I probably won't be worrying much about the skills that required modding to get legendary.
The obsidian tower I have planned will be circular and peak in a mushroom shape. At the base of the tower will be two oblong reservoirs, one for water, and one for magma. From there a system of pumps will lift liquids through the center of the tower where they will pour from the top.
I plan to leave the land untouched so the tower will appear to rise directly out of the wilderness. This means that the dwarves will be forced to live in constructions built above ground until a few layers of obsidian have been poured. Then they'll deconstruct everything as they move inside. The central pumps will allow me to build upward without marring the landscape, the connection to the magma pipe and the aquifer will be underground. I haven't decided yet if the liquid reservoirs should be above- or below-ground. If above, they'll be hollowed from cast obsidian to match the tower.
Here are the questions I don't have answers for yet:
Should the tower extend below-ground? I've thought of taking it all the way to the lowest z-level of the map, to make the tower as tall as possible. I don't know that I'll need/want all that space. If anyone can suggest a way to cast obsidian in a space with a roof I can start at ground level and work down if I'm dissatisfied with the topside tower. Without one-level obsidian casting technology I will have to pour the lowest level first, which requires more planning.
Can I turn off immigration temporarily? I'm thinking that the six dwarves in the embark crew will be the friends of the supermoody dwarf, who follow him out of curiosity/loyalty and keep him protected and fed, since these petty concerns won't trouble him. I don't want to worry about keeping any other dwarves entertained during construction. I want to have immigrants arrive and live in the fort once it is already started. (The less above-ground housing I have to build, the better.)
Should I play with orcs? Originally I had planned to include them, but if I am going to limit myself to my 7 embark dwarves orcs may be more trouble than they're worth.