The daughter of author Terry Pratchett, who has previously worked on video games such as Overlord, Mirror's Edge and Heavenly Sword, has been involved in the project since its inception.
The former video game journalist brings "a depth and credibility to Lara", according to Crystal Dynamics, helping to shape a heroine "who will really connect with today's gamers".
Speaking ahead of her Comic Con appearance with the Tomb Raider team, Rhianna admitted that re-writing Lara Croft has been one of her biggest challenges.
"I grew up playing Tomb Raider, uncovering the world's secrets and unearthing its treasures; I have lived and died as Lara Croft, but nothing comes close to the challenge of re-writing her," she explained.
"Seldom do we get the opportunity to reimagine and reinvent a legend, so getting my narrative hands on Miss Croft was a once-in-a-life-time opportunity.
"It was going back to the genesis of videogame action heroines and exploring how to make such an iconic character meaningful and relatable for gamers today."
It was recently revealed that Tomb Raider will not just be a single game in the franchise.
Last month it was confirmed that English actress Camilla Luddington would voice Lara Croft in the upcoming reboot.
The game's timed DLC, meanwhile, was earlier revealed to take place after the events of the main campaign.
Tomb Raider will be available on Xbox 360, PS3 and PC worldwide from March 5, 2013.
> Read our full Tomb Raider interview with Crystal Dynamics
> Tomb Raider preview: Lara Croft's new story is uncompromising survival
Watch a trailer for Tomb Raider below:
> Interview: Rhianna Pratchett - Overlord