NPCs composing that spawngroup :

a_goblin_overseer (100%)

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

nurga_126, range=10 (-1477,1549,-300)

a_goblin_spirit_chanter (100%)

nurga_160, range=98 (-1568,1506,-300)

a_goblin_death_caster (50%)
a_goblin_spirit_chanter (50%)

nurga_163, range=59 (-1528,1566,-300)

a_goblin_blackguard (50%)
a_goblin_overseer (50%)

nurga_164, range=54 (-1496,1589,-300)

nurga_165, range=53 (-1458,1590,-300)

a_goblin_death_caster (50%)
a_goblin_spirit_chanter (50%)

nurga_166, range=40 (-1451,1507,-300)

nurga_167, range=45 (-1430,1540,-300)