Conversation so far:
What is Hush?
In the 12-part storyline "Hush".
What is the role of the Riddler in this story?
", it is revealed that Riddler suffers from cancer, which also afflicted the mother of Dr.
Thomas Elliot.
How does this change Riddler's life?
uses one of Ra's al Ghul's Lazarus Pits to rid himself of the disease, and offers Elliot the chance to cure his mother as well.
Does Elliot accept Riddler's help?
Elliott is in fact eager for his mother to die in order to inherit her fortune.
Does Ellliott's mother die?
Elliott, who goes on to secretly become the masked criminal Hush, explains he wants to get revenge on his childhood friend Bruce Wayne.
Why does he want to get revenge?
CANNOTANSWER.
Does he succeed on getting revenge?
CANNOTANSWER.
Are there any other interesting aspects about this article?
When the Riddler threatens to expose Batman's secret identity, the Caped Crusader mockingly labels it an empty threat.

Question: Why does he label it this way?
Self-contained rewrite: Why does the Caped Crusader label Riddler's threat an empty threat?