By Andrew Chen
Answer: NEBULA

The story describes classic stories from Greek mythology with the characters missing, starting with Heracles’s first task of defeating the Nemean Lion. As Heracles is the great-grandson of Andromeda and Perseus, the story then describes how Cassiopeia’s boastfulness and Cepheus’s ineffectiveness required Perseus and his steed Pegasus to save Andromeda from the sea-monster Cetus. Each bracketed number corresponds to a character that is also a constellation of the night sky (numbered in alphabetical order).

The Greek string for each character is a sequence of Bayer designations, the most common way of naming stars in a constellation (e.g. Alpha Centauri). Connecting the dots of each sequence within each constellation constructs a polygon that contains exactly one Bayer star and thus one Greek letter. (See below for examples.)

Extracting these enscribed letters, we get:

ID Story​ ​Order Mythological Figure Constellation Greek​ ​String Enscribed​ ​Star
[6] 1 Nemean Lion Leo αηψοπα ν
[5] 2 Heracles Hercules δπηζδ ε
[2] 3 Cassiopeia Cassiopeia γθχδγ φ
[1] 4 Andromeda Andromeda αζηδα ε
[3] 5 Cepheus Cepheus δξνμζδ λ
[8] 6 Perseus Perseus βπρξεβ ω
[7] 7 Pegasus Pegasus βολτβ μ
[4] 8 Cetus Cetus γδκλγ α

By ordering via the positions that the IDs appear in the story, the extracted letters read “νεφελωμα”, which, translated from Greek, is our solution, NEBULA.