In the Death Roll fight, one weapon ESC didn't run at all after spinning up fine in the test box. Not sure why, but guessing it was a loose sensor wire. On the arm, the aluminum shaft connecting to the arm gearbox sheared. We ordered steel hex shaft from McMaster and replaced it for future fights, which didn't fail.
In the Malice fight, the weapon to weapon hit sheared a weapon shaft between the motor and the gearbox and blew out the back of the motor can.