CALCULATIONS TIME!
1.) The average speed of a submarine is 35 knots, 40mph, or 65km/h. If the average distance between two outposts is 12 hours like you mentioned, that is a distance of about 777.8 kilometers or 420 nautical miles. Using an 8 player game, the furthest one can go before the game recalculates to the other side is about 67 hours, or 4343 km, or 2345 nautical miles. Which means if it is a sphere, the circumference is double that - 8686 km or 5397 (regular) miles. If a perfect sphere, its diameter would be 2765 km (C= PI * diameter), meaning the surface area would be 24,025,397 km^2 (SA = 4*PI*radius^2), or ~40% of the surface area of the moon.
EDIT: comparing it to Jupiter's moon Europa, the planet of Subterfuge is ~60% smaller than Europa, whose surface area is 30,900,000 km^2.
2.) One can assume a perfect sphere with a lack of poles. Best demonstrating this would be taking a ping pong ball and drawing some dots on it. By rotating the ball forward or backwards, you will soon find the same dot appear again after 1 revolution, same with going right or left. Longitude and latitude lines were made by humans to keep track of where they are on the globe in relation to the poles, but that does not mean it has to carry over to other planets, especially those which are perfect spheres and not oblong spheroids.
3.) Drillers are most likely mechanical (fission/fusion powered) robots, as hinted as being able to be reconstructed by engineers (have electric components), expedited faster by Tycoons or foremen (humans can't be made faster, but machines can), or stolen by Thieves (have no human part in protesting being stolen).
4.) Generators most likely produce energy through nuclear fission or fusion, as this does not require burning of fuels, and can generate a lot of power.
5.) "When bombarded with neutrons neptunium-237 is used to produce plutonium-238 which is used for spacecraft generators and terrestrial navigation beacons. Neptunium is also used in neutron detection equipment." - So Neptunium can be used to find neutrons, which in turn allow it to turn into plutonium, which can be used to power spacecraft or other machines! As explained by earlier posts (mrhax), the Apparatus may be a way to power a spacecraft to escape this watery planet to another world! (inb4 Subterfuge: Beyond Earth
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