NPCs composing that spawngroup :

a_goblin_death_caster (50%)

a_goblin_spirit_chanter (50%)

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

nurga_102, range=52 (-1475,1539,-300)

a_goblin_overseer (50%)
a_goblin_overseer (50%)

nurga_126, range=45 (-1477,1549,-300)

a_goblin_spirit_chanter (100%)

nurga_163, range=74 (-1528,1566,-300)

a_goblin_blackguard (50%)
a_goblin_overseer (50%)

nurga_164, range=38 (-1496,1589,-300)

nurga_166, range=83 (-1451,1507,-300)

nurga_167, range=57 (-1430,1540,-300)

va_nurga_508003, range=71 (-1525,1565,-300)

va_nurga_508009, range=40 (-1498,1588,-300)

va_nurga_508013, range=58 (-1431,1538,-300)