NPCs composing that spawngroup :

a_blistering_horror (50%)

a_smoldering_abomination (50%)

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

soldungc2780196, range=45 (543,-380,16)

imp_guardian (50%)
imp_vanquisher (50%)

soldungc2780197, range=60 (542,-342,12)

#Pulsating_Pool_of_Magma (50%)
a_burning_mire (50%)

soldungc2780203, range=56 (611,-329,11)

a_conflagarant_terror (100%)

soldungc2780221, range=71 (598,-310,2)