Heavy attack eliminations have a 40% chance to grant Rockin’ Riff.
Melee
With the arrival of Lars to the game as commander, now the heroes of the Summer event can be used for the BASE Boom, this build can be used if u want to protect the B.A.S.E. with meelee weapons (The page has not yet been updated with Lars so the commander what you see is Penny, imagine it's Lars)