NPCs composing that spawngroup :

#The_Crypt_Spectre (20%)

#The_Skeleton_Sepulcher (20%)

a_crypt_guardian (20%)

a_crypt_spectre (20%)

a_skeletal_watchman (20%)

NPCs spawning around that spawngroup :
(Max range : 100)

charasis_44, range=81 (-271,45,4)

an_undertaker_skeleton (50%)
a_sepulcher_skeleton (50%)

charasis_58, range=72 (-269,25,4)

a_sepulcher_skeleton (100%)
a_sepulcher_skeleton (100%)

charasis_96, range=24 (-351,8,14)

a_sepulcher_skeleton (100%)

charasis_97, range=75 (-408,4,14)

an_undertaker_skeleton (50%)
a_pulsating_bile (50%)

charasis_109, range=94 (-367,-96,5)

charasis_160, range=14 (-332,6,14)

charasis_179, range=56 (-387,10,-139)

a_bottomless_feaster (100%)

charasis_181, range=77 (-257,-22,-122)