NPCs composing that spawngroup :

a_giant_rat (33%)

a_large_plague_rat (33%)

a_putrid_skeleton (34%)

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

befallen_56, range=92 (-365,104,-10)

skeleton_Lrodd (50%)
skeleton_Lrodd (50%)

befallen_45, range=90 (-359,91,-68)

a_ghoul (50%)
a_necro_acolyte (50%)

befallen_44, range=45 (-275,80,-11)

a_necro_neophyte (50%)
a_putrid_skeleton (50%)

befallen_43, range=60 (-319,84,-10)

befallen_39, range=94 (-287,31,-11)

befallen_37, range=19 (-294,127,-10)

befallen_35, range=16 (-282,139,-11)

befallen_34, range=82 (-334,183,-11)

a_putrid_skeleton (50%)
a_shadowknight (50%)

befallen_33, range=70 (-332,166,-12)

befallen_28, range=60 (-216,139,-10)

a_large_plague_rat (50%)
a_putrid_skeleton (50%)

befallen_27, range=75 (-209,162,-12)

befallen_4, range=93 (-216,52,-11)

a_cracked_skeleton (50%)
a_putrid_skeleton (50%)