egomaniac (noun)

1. In the novel, the main antagonist is portrayed as an egomaniac who believes he is superior to everyone else.

2. According to Greek mythology, Narcissus was an egomaniac who fell in love with his own reflection.

3. The opulent mansion was designed with the tastes of an egomaniac in mind, featuring grandiose and extravagant elements throughout.

4. The supervillain in the comic book series is depicted as an egomaniac, constantly seeking power and recognition at all costs.