NPCs composing that spawngroup :

an_elemental_deceiver (50%)

an_elemental_harvester (50%)

Stonesoul_the_Unmoving (50%)

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

hole_26, range=51 (71,516,-323)

hole_35, range=96 (44,387,-347)

#a_ratman_guard (50%)

hole_46, range=88 (62,388,-347)

a_wanderer (50%)
a_wanderer (50%)

hole_79, range=54 (104,523,-322)

a_rock_golem (50%)

hole_92, range=96 (91,374,-347)

hole_153, range=32 (64,481,-347)

hole_154, range=27 (99,443,-347)

a_wanderer (50%)
a_wanderer (50%)
a_wanderer (50%)

hole_165, range=51 (82,520,-347)

a_wanderer (50%)
a_wanderer (50%)
a_wanderer (50%)

hole_166, range=75 (144,527,-323)

hole_167, range=98 (144,555,-323)

hole_176, range=88 (65,387,-333)

a_wanderer (50%)
a_wanderer (50%)
a_wanderer (50%)

hole_188, range=61 (116,527,-322)

a_rock_golem (50%)
a_rock_golem (50%)

hole_197, range=94 (53,555,-347)

a_wanderer (50%)
a_wanderer (50%)

hole_204, range=96 (52,556,-373)

a_wanderer (50%)
a_wanderer (50%)
a_wanderer (50%)

hole_229, range=42 (135,457,-346)

a_rock_golem (50%)

Stonesoul_the_Unmovi_189534, range=75 (168,491,-323)

an_elemental_harvester (50%)
Stonesoul_the_Unmoving (50%)

an_elemental_wizard_189569, range=76 (20,483,-347)

an_elemental_wizard (50%)
bejeweled_elemental (50%)

a_rock_golem_189617, range=78 (63,398,-346)

a_rock_golem (50%)

a_rock_golem_189618, range=49 (72,514,-347)

a_rock_golem (50%)

a_rock_golem_189619, range=24 (74,458,-347)

a_rock_golem (50%)

a_rock_golem_189620, range=56 (79,524,-323)

a_rock_golem (50%)

a_rock_golem_189621, range=22 (98,492,-347)

a_rock_golem (50%)

a_rock_golem_189622, range=20 (100,490,-323)

a_rock_golem (50%)

a_rock_golem_189631, range=85 (145,539,-323)

a_rock_golem (50%)

a_rock_golem_189633, range=78 (171,449,-335)

a_rock_golem (50%)

a_rock_golem_189635, range=90 (180,500,-323)

a_rock_golem (50%)

an_elemental_channel_189673, range=63 (98,533,-321)

an_elemental_channeler (50%)