NPCs composing that spawngroup :

an_eyeless_gnawer (25%)

a_blood_leech (25%)

a_ravaging_burrower (25%)

a_ravaging_burrower (25%)

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

pojustice2010170, range=58 (-1113,-644,-29)

pojustice2010172, range=84 (-1055,-629,-29)

an_eyeless_gnawer (50%)
an_eyeless_gnawer (50%)

pojustice2010175, range=75 (-1176,-645,-28)

an_eyeless_gnawer (50%)
a_ravaging_burrower (50%)

pojustice2010178, range=50 (-1177,-573,-28)

pojustice2010179, range=86 (-1154,-504,-28)

pojustice2010184, range=90 (-1060,-527,-27)