They regrouped to save both match balls, and after a series of tense rallies ending in lets, finally it was the English who hit the tin to keep the title in New Zealand hands.
Landers-Murphy was "delighted and relieved" after the win.
"That was so tough. We were ahead in all the games, I'm just glad that we could stay strong and keep it together at the end," she said.
The Mixed final also featured the defending champions against English opposition, with King and Waters straight back on court with partners Paul Coll and Daryl Selby respectively.
This too went to three games as the Kiwis held sway in the first, taking the lead 11-8, but the English pair pulled back a deficit in the second to level affairs 11-9.
It was all New Zealand in the decider though, as Coll and King stayed ahead, retaining their title 11-6 as Coll drove a ball down the middle for a winner.
"We felt good together again today," said Coll.
"We dropped off a bit in the second, but managed to get early leads in the first and third, which always takes the pressure off.
"We have a great team spirit in the Kiwi camp, it's been a tough week to start the season off, but a lot of fun, and we're obviously delighted to be going back with more gold medals."
In the men's final Australia's Ryan Cuskelly and Cameron Pilley beat Scotland's Alan Clyne and Greg Lobban to claim the title.