Which books on Greek and Roman mythology list the most number of mythological characters?

As I am nowadays saying openly, I worked at the Thesaurus Linguae Graecae for 17 years, 13 which I spent working on word recognition. As a result, I got to know pretty well where all the obscure names were in Greek literature.

In the classical Canon, hands down, the Bibliotheca (Pseudo-Apollodorus).

Among online resources, THEOI GREEK MYTHOLOGY saved my bacon quite often.