This latest result further enhances his glorious homecoming after a season of racing in the United Kingdom.
The MX2 class was the most fiercely-fought of all the categories at the Summercross event, with four or five riders all battling within a couple of bike lengths of one another, the handlebar-to-handlebar racing starting at the drop of the start gate and lasting throughout each of Sunday's five races.
Runner-up to Natzke was Taupō's Wyatt Chase, with Motueka's Josh Coppins, Taupō's Brad Groombridge and Palmerston North's Luke Freemantle rounding out the top five.
The overall win was an "early birthday present" for Natzke, who will turn 21 later this week.
"I'm personally not a fan of the quick fire, back-to-back, short race format they use here and so I was never quite ready straight out of the gate. Whoever was out front fast had the advantage," Natzke said.
"I struggled a bit with that, but the last race was longer and I knew I had been faster all day, so it worked in my favour. It was a really good day for me in the end.
"The bike was awesome, stock standard, straight out of the manufacturer's crate. I'm looking forward to the nationals now, with talent coming from overseas too and I'm excited about that."
The MX1 class was more cut and dried after national MX1 champion Cody Cooper decided the injury he sustained during training on Friday was "too uncomfortable" for him to continue beyond the first lap of his warm-up, clearing the way for Hamilton's Kayne Lamont and visiting Belgian rider Jens Getteman to take charge.
Lamont won the first four of five MX1 races with Kawasaki hero Getteman runner-up each time but Getteman saved his best for last, taking his borrowed, stock-standard Kawasaki KX450F to win the longer-duration final MX1 race of the day.
It was Getteman's first time in New Zealand and the track unfamiliar to him – although he did still qualify fastest – but his Grand Prix racing experience from Europe meant he was able to settle into a good pace in the longer final race of the weekend.
"It was good to win that final race," Getteman said.
"I struggled a bit with the first four races ... the sprint races are something different to what we have in Europe. But overall it was fun. I knew in the longer last race I'd be better.
"I didn't want to go home without having at least one race win. I hope I can come back and race here again."