* If it's the Italian word for "deck of cards", it's pronounced "mat-zee". The "z" sound is like the "s" in "pleasure".
* If it's a name, the pronunciation can vary. It could be "mat-zee", "maz-zee", or even "mah-zee". You'd need more context to know for sure!
Let me know if you have more information about the context of the word "mazzi" and I can give you a more definitive pronunciation.