NPCs composing that spawngroup :

an_inactive_trap (12%)

a_blast_of_heat (12%)

a_magi_construct (12%)

a_singularity (12%)

a_spike_trap (16%)

a_tanglefoot_trap (12%)

a_wave_of_cold (12%)

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

necropolis_39, range=60 (-237,-845,-256)

a_Chetari_Deathbinder (50%)
a_Chetari_worker (50%)

necropolis_40, range=78 (-365,-842,-256)

necropolis_162, range=44 (-274,-911,-255)

a_Chetari_Deathshaper (100%)

necropolis_a_Chetari_Seeker34, range=78 (-364,-841,-255)

a_Chetari_Seeker (50%)
a_Chetari_seeker (50%)

necropolis_an_inactive_trap14, range=0 (-292,-871,-257)

an_inactive_trap (100%)