NPCs composing that spawngroup :

a_goblin_spirit_mystic (100%)

NPCs spawning around that spawngroup :
(Max range : 200)

nurga_25, range=72 (-1891,-1635,-48)

a_goblin_life_stealer (50%)
a_goblin_stabber (50%)

nurga_65, range=127 (-1894,-1834,21)

a_goblin_life_stealer (50%)
a_goblin_spirit_mystic (50%)

nurga_66, range=105 (-1920,-1810,25)

a_goblin_arcane_master (50%)
a_goblin_blight_caster (50%)

nurga_189, range=153 (-1849,-1561,-58)

a_goblin_slave_driver (50%)
a_goblin_slave_driver (50%)

nurga_a_goblin_slavedriver1_takp_import_v0, range=108 (-1921,-1812,28)

nurga_a_goblin_blightcaller58_takp_import_v0, range=129 (-1891,-1836,22)