Great news for those looking to import games over from Japan as Amazon Japan is now shipping video games and video game consoles internationally. The one exception is that it has to be sold by Amazon themselves and not 3rd-party sellers.
Games on the Playstation 4, PS Vita, Playstation 3, Xbox One, and DS are region-free meaning they can be played on any system around the world regardless if the system was bought from North America, Japan, or Europe. Games on the Playstation 2, Nintendo 3DS, Wii, Wii U, and Xbox 360 still have region-lock and will require you to have a system from said country.
The only requirement is you need a Amazon.co.jp-specific account.