He went so far back that his first unsanctioned hit was mistakenly put down to the Bonnano war of the 60s! He and an associate killed some Bonnano associate at the time who was ironically close to rusty - who luckily never found out it was Massino.

I reckon he had way more secrets and way more money hidden away that he never needed to reveal (had no threat of it coming out elsewhere).

The fat rat is also responsible for many many bodies in Canada by putting away rizzuto who helped out at Massinos request in the 3 capo hit in the 80s. The gravity of him flipping is so massive.