Valve's Left 4 Dead 2 has been refused classification by Australia's ratings board, meaning it won't be released in the country in its current form.
In its report the board said the game contained "realistic, frenetic and unrelenting violence".
"The game contains violence that is high in impact and is therefore unsuitable for persons under 18 years to play," it concluded.
Retailers have expressed disappointment that the game, due for release in November, has failed to obtain classification.
"Left 4 Dead 2 was expected to be even bigger than the original version," Gametraders national marketing manager Chad Polley told news.com.au. "We had huge predictions of sales."
The lack of an adult, or 18+, rating for videogames in Australia has long been a contentious issue. An exclusion of such a rating means that all videogames need to be made, or edited, to be suitable for 15 year olds to play.
Left 4 Dead 2's failure to be awarded a rating makes the game the fourth to be effectively banned for sale in Australia this year after Sexy Poker, Necrovision and Risen. Edited versions of Necrovision and Sexy Poker were subsequently released with an M rating after resubmission.