NPCs composing that spawngroup :

a_Delve_drake (50%)

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

delvea3410129, range=77 (843,-1256,15)

delvea3410130, range=0 (833,-1179,15)

a_domesticated_basilisk (50%)
a_domesticated_basilisk (50%)

delvea_monocle_1_35, range=76 (843,-1255,15)

a_Delve_diviner (50%)

delvea_monocle_1_36, range=0 (833,-1179,17)

a_Delve_drake (50%)

delvea_monocle_1_69, range=53 (846,-1231,14)

a_drake_egg (50%)

delvea_monocle_4_17, range=76 (843,-1255,15)

a_Delve_evoker (50%)

delvea_monocle_4_22, range=0 (833,-1179,17)

a_Delve_evoker (50%)

delvea_monocle_5_35, range=76 (843,-1255,15)

a_Delve_diviner (50%)

delvea_monocle_5_69, range=53 (846,-1231,14)

a_drake_egg (50%)

delvea_monocle_6_56, range=76 (843,-1255,15)

a_Delve_drake (50%)

delvea_monocle_6_57, range=0 (833,-1179,17)

a_Delve_diviner (50%)