It seems as if a new version of Shadow of the Tomb Raider is in the works, as an age rating for a game called Shadow of the Tomb Raider: Definitive Edition has been granted by the Australian Classification Board.
Shadow of the Tomb Raider was released in 2018 and it has received seven DLC episodes since launch, as well as individual character and equipment DLC packs. These include The Forge, where Lara has to explore a cave that is overflowing with magma and The Nightmare, where Lara has to enter a nightmarish version of Croft Manor and face an evil version of herself.
There have been several leaks regarding a possible definitive edition of Shadow of the Tomb Raider, but the game seems to have been confirmed by a recent age rating that was requested from the Australian Classification Board. The listing for a game called Shadow of the Tomb Raider: Definitive Edition can be found on the organization's website and it was granted on October 3, 2019.
Shadow of the Tomb Raider: Definitive Edition has been given an M15+ age rating in Australia, due to the game's strong violence, moderate language and themes, and mild nudity. This is the same age rating that the original Shadow of the Tomb Raider received back in 2018.
Shadow of the Tomb Raider was well-regarded upon release, but the consensus was that it wasn't as impressive as the previous two entries in the series. It didn't help that Shadow of the Tomb Raider was released shortly after Marvel's Spider-Man, which was a game that dominated the headlines for several weeks following its release. It's possible that Shadow of the Tomb Raider: Definitive Edition might find a more receptive audience if it's released during a less packed season than the original version of the game.
Shadow of the Tomb Raider: Definitive Edition is listed as being a multiplatform release, which means that it will likely be released for PlayStation 4, PC, and Xbox One. The new trilogy of Tomb Raider games has been confirmed for Google Stadia, so it's possible that Shadow of the Tomb Raider: Definitive Edition will be released for that platform as well.
Source: Australian Classification Board