Colonnello

コロネロ

Holder of the Blue pacifier.
Colonnello oversees the training ground behind Mafia Land and is a former member of the COMSUBIN, an elite Italian Navy unit. He acts as a rival to Reborn, and the feeling is mutual; they often dismiss each other's attacks as weak before proceeding to strike one another. Despite their rivalry, he shares several traits with Reborn, such as being a merciless tutor, taking sudden naps, and possessing a sharp tongue. He also ends his sentences with a "hey."
As a former military member, Colonnello is not averse to using heavy artillery; he managed to destroy an entire fleet of ships with a single anti-tank rifle. This aligns well with his name, which means 'colonel' in Italian. Additionally, an eagle perched on his head allows him to fly to distant locations in a short amount of time. It also appears to be in sync with Colonnello: when he naps, the eagle naps.
During the Vongola Tournament, he becomes Ryohei's home tutor and actually lives in his house. In the future, it is revealed that, as an adult, Colonnello followed the original seven Arcobaleno on the day they were turned into babies, attempting to take Lal's place. This resulted in him attaining the blue pacifier meant for Lal, and consequently turning Lal, who was his former instructor in the COMSUBIN, into an incomplete Arcobaleno.

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