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"The plan is to have everyone gather at the stage on the Lakefront then pretend to do normal stuff, like playing touch, having a family picnic, then somebody will stand up and start the haka and everyone stops what they are doing and joins it. "
She said the flash mob was also a personal competition between her and her family in Australia.
"I have family in Australia who have been saying their flash mob will be better than mine so I have to beat them," she laughed.
To take part in the flash mob haka meet Ms Walker-Poroa at the stage on the Lakefront at 12pm. Everyone has been asked to wear black.