Cyberpunk 2077, a video game reported to be one of the most expensive ever made, launched worldwide on Thursday after its makers vowed to fix graphics that risk triggering epileptic seizures.

Despite a publicity blitz worthy of a Hollywood film, the run-up to the debut has been anything but smooth.

The release has been delayed twice this year and the developers were forced to add health warnings after one reviewer complained it had caused an epileptic seizure.

Game producer CD Projekt RED said it was looking into a "more permanent solution" to tackle the health risk "as soon as possible".

Entertainment rating website Metacritic has given the game a score of 91 out of 100 based on 50 reviews, describing it as "an open-world, action-adventure story set in Night City, a megalopolis obsessed with power, glamour and body modification."

Reviewers said the game was deeply immersive and praised its portrayal of a futuristic cyber city, as well as the freedom given to players.

But many also pointed to bugs in the game and the poor quality of graphics, reigniting a debate about developers selling an unfinished product at full price.

"On the standard PS4 (gaming console) the graphics on this game look horrible. I can't stand it," Polish gamer Michal Muszynski said, quoted by the local Komputer Swiat (Computer World) website.

Marcin Iwinski, director and co-founder of the game's Polish developers CD Projekt RED, told AFP that gamers could expect a "new quality" of experience when they enter its dystopian world.

Iwinski said the studio had created an "immense" online world. The English language version has 450 hours of dialogue voiced by 125 actors.

The main character of Cyberpunk 2077 is the gun-toting "V", who makes his way through Night City -- a conflict-ridden American megacity.

The game also features the face and voice of Hollywood star Keanu Reeves, best known for the "Matrix" trilogy and "John Wick".

An imaginable reality

The budget for the game is estimated at 1.2 billion zloty ($328 million), according to analysts at Polish bank BOS, which would make Cyberpunk 2077 one of the most expensive video games ever made.

CD Projekt RED's hugely successful "The Witcher: Wild Hunt" was a sombre fantasy whose monster-slaying hero endowed with superhuman powers was a product of the imagination of Polish writer Andrzej Sapkowski.

It was launched in 2015 and is still much loved by gamers for its storyline, dialogue, graphics and humour, as well as the openness of its world.

"The Witcher" propelled CD Projekt RED's stock value to a whopping 42.7 billion zloty, ($11.6 billion), allowing it to vie with France's Ubisoft for top spot among European gaming developers.

CD Projekt RED is betting that the punk fantasy world of Cyberpunk -- the popular pen-and-paper role-playing game written by Mike Pondsmith -- will be an even greater hit.

The marketing campaign featuring yellow posters with "V" reached 55 countries and media reports estimated its budget ran into the tens of millions of euros.

The developers blamed the delays this year on the coronavirus pandemic and the complexity of creating such a vast world for nine different platforms.

"We are an innovative company and it is not in our DNA to take shortcuts," said Iwinski.

He pointed in particular to the widespread use of futuristic cyberware in the game, calling it "an imaginable reality" before adding: "We'll see if it turns out like that".