What was connected to this circuit? It should't blow up traces by itself. My guess is there was something connected which have current path to earth. I hope you did not attach an oscilloscope to it.
see attached, it was floating in the air held by the helping hand by the mains cord... nothing connected, just the mains cord to the circuit. i was just testing for circuit stability when connected to the mains, about a second later, boom! btw, i know how to probe this safely dont worry people, i got shocks since i'm very little i'm very well aware of the danger to the point of all my kids are too scary when come close to a naked wire sigh
... the circuit was not probed yet, as i said, only stability test...
attached is the circuit i'm working on. nevermind other components they are not populated yet... only fuse, D1, R3, D2 (zener), and C2 and the mains cord (2 wires cord) are populated. do i have with copper pour clearance issue? i dont thing so, since the blast points are along the path of D1,R3,D2 (see 4th picture, i reattached the broken traces ready for the next blast?
but waiting for the counsel verdict here). only D2 zener is dead, D1 and R3 still ok... fwiw...