NPCs composing that spawngroup :

an_undertaker_skeleton (25%)

a_sepulcher_skeleton (25%)

a_sepulcher_spectre (25%)

elementalbone_skeleton (25%)

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

charasis_34, range=91 (-409,-405,5)

#The_Crypt_Excavator (50%)
a_helot_spectre (50%)

charasis_36, range=31 (-373,-326,4)

charasis_37, range=15 (-387,-314,5)

a_bottomless_devourer (100%)

charasis_39, range=66 (-387,-250,4)

a_sepulcher_skeleton (50%)
a_sepulcher_skeleton (50%)

charasis_40, range=29 (-375,-301,4)