NPCs composing that spawngroup :

a_shrieker (100%)

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

thedeep1312253, range=46 (-770,141,-64)

thedeep1312252, range=91 (-636,149,-94)

An_Enthralled_Underbulk (20%)
An_Enthralled_Underbulk (80%)

thedeep1312251, range=78 (-650,172,-93)

an_enthralled_outcast (50%)
An_Enthralled_Razorfiend (50%)

thedeep1312246, range=40 (-753,127,-65)

a_shrieker (34%)
a_shrieker (33%)
a_shrieker (33%)
a_shrieker (34%)
a_shrieker (33%)
a_shrieker (33%)

thedeep1312017, range=89 (-640,180,-94)