NPCs composing that spawngroup :

a_bottomless_feaster (50%)

greater_war_boned_skeleton (50%)

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

charasis_114, range=38 (-42,444,22)

charasis_116, range=89 (7,531,22)

charasis_123, range=99 (3,549,21)

a_bile_golem (50%)
a_bile_golem (50%)

charasis_124, range=46 (-62,429,21)

a_bile_golem (50%)
a_sepulcher_skeleton (50%)

charasis_128, range=90 (-144,518,3)

a_bile_golem (100%)

charasis_129, range=76 (-116,532,14)

charasis_134, range=82 (-132,429,22)

charasis_143, range=95 (-144,423,22)

a_sepulcher_skeleton (100%)

charasis_208, range=95 (-127,548,4)

greater_war_boned_skeleton (100%)