Here are the screenshots and stats of the Boss Fights from Italy Region 6: Calabria
BOSS: Don Vittorio Messino
Bronze Mastery Level:
After completing the six Energy Path jobs, you can fight the Calabria Boss - Don Vittorio Messino.
At Bronze level, this Boss is very easy to defeat. You have a henchman; he does not. It took one Shiv and one Attack to end the fight.
Once you defeat Don Vittorio Messino, you earn Messino's Pistol (115A/85D) at Bronze Level.
Silver Mastery Level:
Don Vittorio Messino starts with 5,000 health...
Your new title for defeating Messino is Calabrian Forte
At Silver Level, Messino's Pistol has stats of (135A/96D) - an improvement of 20 attack and 11 defense points from Bronze Level.
Gold Level Mastery
Now, Don Vittorio Messino starts with 16,000 health. You still have one henchman. He has none.
Your title upon defeating the Gold Level Boss is Calabrian Potente.
At Gold level, Messino's Pistol has stats of (155/107) = another 20 attack and 11 defense better than the Silver Level reward.