NPCs composing that spawngroup :

a_fog_golem (50%)

greater_plaguebone (25%)

greater_plaguebone (25%)

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

citymist_a_phantom39, range=71 (182,-350,65)

a_phantom (50%)
a_phantom (50%)
a_phantom (50%)
a_phantom (50%)

citymist_a_mist_golem7, range=42 (211,-307,274)

a_mist_golem (100%)

citymist_greater_spurbone86, range=53 (262,-378,39)

greater_spurbone (50%)
greater_spurbone (50%)

citymist_222961, range=23 (243,-349,-15)

citymist_222966, range=39 (242,-365,41)

citymist_222969, range=51 (198,-334,-11)

citymist_222972, range=14 (262,-333,-15)

citymist_222977, range=97 (162,-283,75)

citymist_222982, range=9 (258,-329,77)

a_mist_golem (50%)
a_phantom (25%)
a_phantom (25%)

citymist_222984, range=74 (210,-389,274)

citymist_222985, range=85 (199,-395,273)

citymist_222986, range=30 (219,-327,273)

citymist_222988, range=60 (189,-324,274)

a_fog_golem (50%)
greater_war_boned_skeleton (50%)

citymist_223157, range=13 (260,-333,240)

gyrating_goo (100%)
gyrating_goo (100%)

citymist_223158, range=37 (279,-348,75)

gyrating_goo (50%)
gyrating_goo (50%)