We do know that Crystal Dynamics is working on the follow-up title to Rise of the Tomb Raider. However it was announced today that Rhianna Pratchett is not going to be involved in the next game.
The official Tumblr page announced the following: “Crystal Dynamics and Rhianna Pratchett are announcing today that Rhianna is off to pursue new adventures separate from the Tomb Raider franchise. Rhianna was instrumental in helping us find Lara’s voice in the 2013 origin story, and through Rise of the Tomb Raider she shaped Lara into the evolving heroine we know today. The entire team thanks Rhianna for her dedication and tireless efforts on the games. Please join us in wishing Rhianna the absolute best in her next adventure.
Rhianna Pratchett was the lead writer for both Tomb Raider 2013 and Rise of the Tomb Raider. It appears the new game will have a new writer due to her departure. It will be interesting to see the other game she will be working on. Crystal Dynamics says she is now working on a “new adventure”.