NPCs composing that spawngroup :

a_goblin_overseer (50%)

a_goblin_overseer (50%)

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

nurga_99, range=70 (-1193,580,-189)

a_goblin_flame_chanter (50%)
a_goblin_spirit_chanter (50%)

nurga_100, range=66 (-1105,528,-189)

a_goblin_death_caster (50%)
a_goblin_spirit_chanter (50%)

nurga_101, range=44 (-1128,499,-189)

va_nurga_508013, range=1 (-1171,512,-188)