The utility back has spent his entire professional career with the union, but has agreed a move to Waikato for 2006.
Muliaina was impressive in his first NPC start of 2005, the semi-final defeat of North Harbour.
And he is grateful for a final chance to play in a high-profile game for the Auks.
"I'm obviously excited about it," he told The Dominion Post. "I have the opportunity to go out on a bang, so I'm looking forward to it.
"It was a pretty emotional time last week - the days were getting less and less," he said.
"But seven years in the blue-and-white hoops, I can't complain about that. They've been awesome years and I've managed to play with some great players."
But, the 26-year-old, capped 33 times by the All Blacks, added: "I'm at that stage of my rugby career where I need another challenge, a new beginning, I suppose.
"There's some exciting talent down there, some guys I'm really looking forward to playing with."
However, Auckland coach Pat Lam proposed the star may return to the province one day.
"Who knows what could happen?" he asked. "We've seen Junior Tonu'u come back. "But I haven't looked that far ahead."