NPCs composing that spawngroup :

#invis_johanius_eleven (72%)

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

tenebrous1376033, range=96 (23,1749,-36)

tenebrous1376032, range=80 (80,1747,-35)

tenebrous_104145, range=45 (84,1782,-37)