Other acts on the hip-hop and dance-friendly bill include Chali 2na, DJ Marky, Mala, Homebrew, Ladi6, Machinedrum, Danny Byrd, Swindle, A-Sides, Skeptical, Dub Phizix + Strategy, State Of Mind + MC Woody, Dylan C, K+Lab, DLR, Bailey Wiley, Midnight Gallery, Tali, Diaz Grimm, 48 Sonic, Totems and Randa.
More international acts will be confirmed in a second line-up announcement.
Festival director Gareth Popham says the the festival has expanded after demands from fans.
"The idea of adding the 29th came after we received requests from a large portion of our audience to extend their Northern Bass experience," he says.
And he's happy with the headliners: "Getting to see Shapeshifter perform on the Northern Bass main stage has always been a long-term goal of mine."
Tickets are on sale through www.iticket.co.nz
See tomorrow's TimeOut for more major music festival announcement for the spring and summer.