Gank

Gank (to gank) The act of defeating a defending fighter in a quick, brutal, humiliating, or effortless manner with one or more people attacking simultaneously.

Ganked (to be ganked) The event in which one is attacked and defeated in a quick, brutal, humiliating, or effortless manner by one or more people attacking simultaneously.

i.e. "Dude, did you see that Ruben and his posse just totally ganked Dagmar?"

i.e. "I was out on the field and got ganked by some BOF."