Before getting into the top two, Pia and Baden had to fight alongside Harry for the final immunity necklace.
The trio were put onto pedestals where they had to hold idol weights without letting them drop. After six hours and 40 minutes, Harry stopped first, then Pia but Baden held strong.
Baden won the challenge and the immunity spot to the grand final but made the error of taking Pia with him.
Pia and Baden both pleaded their case to the nine members of the jury, but it was Pia who came out on top securing all nine votes.
"I'll be first out... or I'll win," she said at the start of the season adding, "I really believe that." And she wasn't wrong.
Despite her tough exterior, the Aussie star’s time on the survival show nearly broke her.
The Looking for Alibrandi star has confessed she felt like she was left with post traumatic stress disorder (PTSD) after her stint in Fiji.
"I honestly felt like I had a bit of PTSD," before admitting she even began to think her own family was "plotting against her,” she told a local Australian publication.
"I told myself, 'My family isn't plotting against me,' but some days I'd struggle to look them in the eye," Pia added.
"I kept saying, 'I have to keep an eye on everyone.' But I was just being paranoid."
The star's struggle to adjust back to normal life was so immense that she was unable to use an inside toilet at first, instead choosing to go outside behind a tree.
Pia recently faced heavy backlash from fans after she was accused of cheating on one of the show’s challenges.
The contestants were challenged to hang onto a bar for 90 minutes, first with both hands, then with two. In the final moments, Simon slipped off taking himself out of the challenge and soon after Luke did the same. However, in-between Simon and Luke bowing out of the challenge, eagle-eyed viewers spotted Pia appearing to grip the bar with both hands.
Taking to Instagram, Pia - who recently opened up about the shock medical condition she was diagnosed with during filming - attempted to clear up the controversy.
"In regards to the edit showing me apparently changing arms," she wrote, "I was changing them throughout the challenge when it was 2 arms to give each one a rest. I can only assume vision came from that period of the challenge."