Savea helps All Blacks extend winning run over Wales
The All Blacks, who have not lost to the Welsh since 1953, led 22-13 at half-time thanks to two short-range power tries from hooker Cody Taylor.
Wales hit back with a try by debutant winger Rio Dyer converted by Gareth Anscombe, who also nailed two penalties, but a Jordie Barrett try gave the All Blacks some breathing space at 22-13 at the break.
Although Wales skipper Justin Tipuric scored a second try in the second period, it was all about the visitors, with Aaron Smith bagging himself two tries in quick succession, followed by Savea, Jordie Barrett (for his second) and replacement hooker Samisoni Taukei'aho.
By their own high standards, New Zealand have had a varied season, losing a home summer series 2-1 to Ireland and, despite going on to win the Rugby Championship, suffering a first home loss to Argentina.
But there was no such febrility on show in the Welsh capital, an effective midfield blitz defence and an outstanding hard-nosed backrow performance, with man-of-the-match Savea and Dalton Papali'i to the fore, nullifying any real threat Wales posed.
Searing break
Mo'unga opened the scoring with an early penalty in a helter-skelter start to the game.
A searing break by Papali'i into the Welsh 22m area saw New Zealand set up a series of pick and go's, Taylor eventually driven over for the game's opening try, Mo'unga converting.
There was more of the same shortly after Wales strayed offside. Mo'unga kicked to the corner, the All Blacks rolled the line-out into midfield and proceded to batter the home defence until Taylor burrowed his way over for his second try.
Mo'unga converted and Wales were 17-0 down after the opening quarter. Wayne Pivac's team were given hope when Dyer claimed a try back after a smart mismove and slick Nick Tompkins pass off an attacking lineout.
Anscombe, pushed into the fullback role from fly-half after the late withdrawal of Leigh Halfpenny, converted.
A Tompkins dart from an unguarded ruck led a scrambling All Black defence into offside, Anscombe kicking the penalty.
New Zealand scored their third try of the opening half through Jordie Barrett, the inside centre outjumping Dyer to field a towering Mo'unga crosskick, twist and touch down.
The last word of the half went to Anscombe, who booted a second penalty to leave it 22-13 in New Zealand's favour.
Wales opened the second period as they needed to, Tomos Williams fly-hacking deep into All Black territory and Taulupe Faletau doing well to track down Beauden Barrett, an ensuing penalty duly kicked by Anscombe.
But Aaron Smith then celebrated his 113th Test - surpassing Dan Carter as the most capped All Blacks back -- by stepping inside Tommy Reffell and Anscombe for a fine sniper's try converted by Mo'unga.
Wales kept in touch as Tipuric pounced on a Tomos Williams chip Mo'unga failed to gather, Anscombe converting to make it 29-23.
New Zealand fired straight back, however, Savea producing possibly the most outrageous dummy of the year to get past Tipuric and offload to Smith, the scrum-half going over for his second try.
Savea then pounced for New Zealand's sixth try as Wales battled to stay within sight.
Mo'unga produced a try-saving tackle to haul Anscombe into touch after Beauden Barrett saw his effort to control an up-and-under bobble away from him.
That proved to be Wales' last proper offensive foray as Jordie Barrett nabbed his second thanks to a great pass from brother Beauden, who also converted.
Taukei'aho crossed for New Zealand's eighth try of the game with large swathes of the crowd having already left the stadium, and leaving Wales to go back to the drawing board.