The 2020 comic is being turned into a God of War-like action title.
Comic art showing an adult mutant ninja turtle wearing a black mask and wielding several different samurai weapons.

What some claim is the "darkest" comic series involving the Teenage Mutant Ninja Turtles is being turned into a video game. Teenage Mutant Ninja Turtles: The Last Ronin is set to be a third-person action focused adaptation of the 2020 comic series of the same name. Like the comic, this game will be a darker and more mature take on the Turtles.

Polygon is the first to share this announcement thanks to a recent chat with Doug Rosen, the senior vice president for games and emerging media at Paramount Global. In this interview, Rosen compared the upcoming game to the third-person action-RPG style seen in the recent God of War titles. The Last Ronin will stick rather closely to the source material, and will be set in a future in which only one of the Turtles survived.

Though The Last Ronin will mostly be a single-character game, Rosen says that other characters could be playable via flashback sequences. This again is similar to how the comic handles the lack of the other Turtles in this universe.

The identity of which of the Turtles was the lone survivor remained a mystery up through most of the comic release. If you do not want to know any major spoilers, I suggest skipping over the spoiler below as quoted from Polygon.

The identity of that lone remaining Ninja Turtle was something of a mystery when The Last Ronin comic series was announced. The arc’s story was built around a Ninja Turtle who wore a black mask and fought using all four turtles’ signature weapons: nunchaku, sai, bo staff, and dual katanas. It wasn’t until the final pages of the first issue of The Last Ronin where the lone surviving turtle’s identity was revealed: Michelangelo. The remaining turtles, and Master Splinter, have all been exterminated by the Foot Clan, leading Mike to seek justice for their deaths in a battle-ravaged New York City.​
It's nice to see the objectively best Turtle is the lone survivor. Yes, objectively.

The Last Ronin comic series spans five-issues. The story arc was written by Kevin Eastman, and is based on an idea that he first conceived with TMNT co-creator Peter Laird back in the late 1980s.

Teenage Mutant Ninja Turtles: The Last Ronin is still a "few years off" from being released. Rosen says to expect more details on The Last Ronin, along with other TMNT video games, to be shared in the months and years ahead. IDW Publishing is actually working on a second comic series called The Last Ronin: The Lost Years and will fill in some gaps in the Ronin's life and act as a sequel to the first series.