NPCs composing that spawngroup :

greater_spurbone (50%)

greater_spurbone (50%)

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

citymist_46, range=65 (66,65,2)

citymist_55, range=83 (24,-45,2)

citymist_66, range=53 (143,-6,274)

a_deranged_madman (50%)
greater_plaguebone (50%)

citymist_67, range=65 (31,-24,274)

greater_war_boned_skeleton (100%)

citymist_74, range=75 (150,-42,273)

citymist_119, range=55 (140,-21,-9)

a_shadow (20%)
greater_spurbone (20%)

citymist_133, range=88 (13,46,28)

greater_plaguebone (25%)

citymist_172, range=72 (102,-67,2)

citymist_223157_takp_import_v0, range=35 (80,-29,273)

gyrating_goo (100%)

citymist_222990_takp_import_v0, range=50 (139,19,273)

a_mist_golem (50%)
greater_war_boned_skeleton (50%)

citymist_222973_takp_import_v0, range=89 (13,49,28)

a_fog_golem (50%)
a_vapor_golem (50%)

citymist_222974_takp_import_v0, range=25 (116,-1,3)