NPCs composing that spawngroup :

a_netherbian_flesheater (1%)

a_netherbian_hive_fiend (1%)

a_netherbian_ravager (98%)

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

umbral1408286, range=77 (1307,1173,2)

umbral1408044, range=56 (1272,1193,1)

umbral_288171, range=77 (1307,1173,2)

a_gargantuan_zelniak_# (100%)

umbral_288233, range=0 (1286,1248,1)

umbral_288234, range=56 (1272,1193,1)

umbral_288253, range=77 (1307,1173,2)

a_gargantuan_zelniak_### (50%)
a_gargantuan_zelniak_### (50%)