Possible Clues:

• Mario Kart character
• Nintendo character in a green hat
• Nintendo brother
• One of the Mario Brothers
• He wears green and eats mushrooms
• Fictional brother with a green hat
• Author Pirandello
• Dramatist Pirandello who wrote 'Six Characters in Search of an Author'
• Italian with alluring air oddly rejected
• Italian dramatist Pirandello