NPCs composing that spawngroup :

an_ice_goblin (50%)

a_goblin_priest (50%)

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

permafrost_1, range=60 (240,-316,3)

permafrost_15, range=65 (288,-374,4)

a_goblin_evoker (50%)
a_goblin_prelate (50%)

permafrost_18, range=61 (311,-370,4)

permafrost_19, range=70 (348,-361,3)

permafrost_80, range=85 (381,-283,3)

an_ice_goblin (50%)
a_goblin_prelate (50%)