NPCs composing that spawngroup :

an_amorphous_mass (100%)

NPCs spawning around that spawngroup :
(Max range : 200)

necropolis_42, range=11 (1338,927,-100)

an_amorphous_mass (50%)
an_amorphous_mass (50%)

necropolis_44, range=166 (1430,1052,-122)

an_amorphous_mass (50%)
an_amorphous_mass (50%)

necropolis_48, range=172 (1502,935,-146)

an_amorphous_mass (50%)
an_amorphous_mass (50%)

necropolis_49, range=164 (1494,927,-148)

an_amorphous_mass (50%)
an_amorphous_mass (50%)

necropolis_50, range=92 (1384,844,-90)

an_amorphous_mass (50%)
an_amorphous_mass (50%)

an_inactive_trap_190119, range=154 (1366,769,-82)

an_inactive_trap_190120, range=114 (1371,1026,-106)

a_swarming_beetle_190140, range=34 (1362,932,-101)

an_empty_nest (25%)
a_nest (75%)