Lucky Luciano setting up both Joe the Boss and Maranzano.

The 3 Bonanno Capo's murder. Came for peace. Ended up dead.

Didn't Carmine Galante get killed by some of his own bodyguards?
If so I would consider that a betrayal.

Wild Bill Cutolo getting killed long after the Colombo wars of the early 90's were over because the rival faction was afraid of his power.

Just a few of the top of my head.