gang up on (?.)

• ambush
• assail
• assault
• attack
• blitz
• bushwhack
• come at
• come down on
• crack down on
• descend on
• descend upon
• fall on
• fall upon
• go at
• go for
• harry
• have at
• hit
• hit like lightning
• jump
• land on
• lay at
• lay hands on
• lay into
• light into
• mug
• pitch into
• pounce upon
• pound
• sail into
• set on
• set upon
• strike
• surprise
• swoop down on
• take the offensive
• wade into