What’s CERO Z, you say? It’s the Japanese "adults only" rating for video games with excessive gore. CERO Z titles are held behind counters and retailers check your ID before selling the game to you. When the CERO Z rating was first added in 2006 it was taboo and some developers edited content to get a CERO D (17+) rating. That’s one of the reasons why Tecmo Koei removed decapitations from Ninja Gaiden Sigma.
The CERO Z rating is more common nowadays since more Western games are localized for Japan. Wii U will actually launch with a CERO Z game – Ninja Gaiden 3: Razor’s Edge. Wii had Red Steel, a CERO C (15+) title, as a launch game for Japan. The Nintendo 3DS launch line up in Japan only had CERO A and CERO B games.
Nintendo has taken steps in Japan to reach out to older gamers starting while keeping their family friendly image. They funded the ultraviolent giant slaying game Zangeki no Reginleiv from Earth Defense Force developer Sandlot. At the same time, Nintendo required all Wii and Nintendo 3DS games rated CERO C and had to be packaged in easily identifiable black boxes. They are the only hardware manufacture in Japan to do this. This balanced approach allows Nintendo to develop games that target adults like Bayonetta 2 without shedding their family friendly image.