69
civilization
|
19
gravity
× 2 |
7
transportation
|
4
materials
× 3 |
69
dinosaurs
|
12
hard-science
× 2 |
7
prison
|
4
natural-disasters
|
69
medieval
|
12
military-defense
|
7
ships
|
4
asteroids
|
69
protection
|
12
bronze-age
|
7
relativity
|
4
alternate-history
|
54
antimatter
× 3 |
12
cataclysms
|
7
psionics
|
4
prehistoric-times
|
50
energy
× 2 |
12
space-constructs
|
7
warfare
|
4
rogue-planets
|
47
planets
× 4 |
12
terraforming
|
5
technology
× 2 |
4
stoneage
|
42
xenobiology
|
10
physics
× 4 |
5
time
|
3
environment
× 3 |
42
alternate-reality
|
8
astrophysics
× 2 |
5
time-travel
|
3
universe
|
42
biochemistry
|
8
generation-ships
|
5
precognition
|
2
metals
|
40
science-based
× 8 |
7
magic
|
5
hacking
|
2
atmosphere
|
39
science-fiction
× 3 |
7
astronomy
|
5
computers
|
2
chemistry
|
39
black-holes
× 2 |
7
transport
|
4
reality-check
× 5 |
2
climate
|