subterranean [Adjective] + cavern [Noun]

Strength Strength Dispersion
A:
3
CHISQ:
1,038.46
AWT:
46,784,810
TTEST:
1.73
G2:
41.14
FAWT:
1.16
MI:
8.44
LOGLOG:
13.38
JD:
0.25
MI3:
11.61
DICE:
1.45
RANGE: