when confronted with multiple attackers your best defense is your back to the wall and a good rifle with 20-30 rd STANDARD capacity mags. A pistol if you can't have a rifle.
A good knife is a must. Preferably a fixed blade, Kbar being ideal but something more discreet may be desired for formal occasions.
Assisted openers are a good second choice.
And don't forget the flashlight.
All the martial arts training done with boots and gloves means nothing in an encounter with half a dozen crips, bloods or zetas that want your nice, new shiny SUV along with your wife and 2 teenaged daughters.
Who carries a rifle on their person during every-day situations? Many localities and states forbid concealed and open carry of pistols.