95
reality-check
× 15 |
27
alternate-history
× 2 |
17
security
|
10
western
|
73
science-based
× 10 |
26
politics
× 3 |
16
electricity
× 4 |
10
metals
|
69
warfare
× 9 |
26
space
× 3 |
16
transportation
× 2 |
10
feudalism
|
64
society
× 11 |
21
computers
|
16
modern-age
× 2 |
9
medieval
× 3 |
52
economy
× 15 |
21
history
|
15
cities
× 2 |
9
geography
|
50
physics
× 2 |
20
weapons
× 5 |
13
environment
× 3 |
9
vehicles
|
49
technology
× 7 |
20
robots
× 2 |
13
construction
|
8
near-future
× 4 |
41
magic
× 3 |
20
united-states
|
13
death
|
8
taxes
× 3 |
33
government
× 6 |
19
clothing
|
13
teleportation
|
8
pre-industrial
|
31
technological-development
× 2 |
19
crime
|
12
culture
× 2 |
8
engineering
|
30
chemistry
|
17
space-travel
× 2 |
12
aliens
|
7
renaissance
|
30
fire
|
17
colonization
|
10
hard-science
× 2 |
6
power-sources
× 2 |
29
generation-ships
× 2 |
17
underground
|
10
science-in-society
|
6
humans
× 2 |