1d20 Cave Hazards

1 Random hole (1 vertical, 2 steep-sided, 3 giant cenote, 4 ankle-breaker)

2 Chasm (1 deceptively wide, 2 jumpable(?), 3 narrow, 4 bottomless)
3 Sheer cliffs
4 Undermined passage
5 Narrow squeeze
6 Dead end
7 Lost mineshaft
8 Flooded passage
9 Flash flood
10 Rockfall
11 Earthquake
12 Bad air (1 blackdamp (CO_2), 2 whitedamp (CO), 3 stinkdamp (H_2S), 4 afterdamp (CO +))
13 Firedamp
14 Radioactive ores and irradiated stone
15 Guano and ammonia fumes
16 Toxic mold and spores
17 Hot springs and vents
18 Ant hive (1 stinging, 2 biting, 3 stinging and biting, 4 harmless but gross)
19 Giant ant hive
20 Carnivorous naked mole rat colony

(This list is included in Red Solstice vol. 2, available now from Spear Witch!)