Rousey's remarkable body transformation since her stunning KO defeat to Holly Holm at UFC 193 in Melbourne last year was highlighted last week. She has since shared several other impressive training images to her Instagram.
Opinions have varied wildly on how Rousey will perform, after more than a year out of the Octagon and with other parts of her career having taken priority recently.
Yet, the former Olympic judo medallist insists this fight, for which she has shunned the most media and public commitments, has her full attention, given it's her shot at redemption for the Holm loss.
"Fighting is my life and I need to do it again," she told a Countdown to UFC 207 special.
"After going through all of that [defeat], I have a much bigger point to make this time.
"I have more experience [than Nunes] being under the most pressure possible and the pressure's different. I'm still the greatest fighter in the world."
However, Rousey admitted she still "grieved" the Holm loss and its ramifications.
"I'm still grieving the person that could have won it all," she said. "But I have to live up to the fact that I'm not her, that's just who I'd like to be.
"And instead I'm what I need to be for myself and everyone else. You have to go through those stages of acceptance and renewed optimism.
"I'm coming back to win this title for the people that believed in me. Everything in my whole life that I've always worked for, everything depends on it.
"Everything is at stake."
Rousey said she had keenly felt the criticism that followed her UFC dethroning.
"I hear so many of the worst things anyone could ever even imagine to say about me every single day," she said.
"Thousands of times, people are trying to reach me and say these negative things. People like to see people rise, because they want to see people fall, because they want to feel like they're human like they are.
"That's why we have this cycle of raise people up and then we crash down."
