built according to stolen prototype blueprints - by no means, in success or failure, must the operation be traced back to the United Nations. However, for all this secrecy to be effective, even in victories the assault choppers will have to be destroyed... and the pilots killed. However, to compensate for their sacrifice, the UN shall fulfill one of their wishes, no matter what it is. And this, on board a stolen EVAC carrier plane, is how the story begins... Later releases Arika, developer of the PlayStation 2 ports for DoDonPachi DaiOuJou and Espgaluda, had expressed interest in porting Ketsui to the PlayStation 2 as well. However, they claimed that the console was insufficient for achieving the arcade-perfect quality they sought. Specifically, the second half of stage 5 employs a quick swap of the entire background plane, coupled with reversing the overall scrolling direction ("tate-ana"). Arika claimed that this was unachievable with the standard amount of RAM and processing power of the PlayStation 2. Mobile versions In 2003, Cave released a mobile phone version of the game as two separate titles, available for imode (for 504/505/506 and FOMA90*i series) and Yahoo platforms. A DX version for FOMA 900 and 901 was released in 2004. The EZWeb version was released in 2005. Danmakukenteishiken Ketsui Hen (弾幕検定死験 -ケツイ編-) is a spin-off title based on Ketsui, released in 2006 for imode. This version is a boss battle version of the game, emphasizing on dodging bullets. The player's goal is to earn ranks by repeatedly defeating the same boss, but with increasing difficulty in successive runs. Nintendo DS release On 2007-3-26, Arika's vice president Ichiro Mihara mentioned the release of Nintendo DS version of Ketsui in his personal page . The game, subtitled Death Label, was available for download in test events on March 31, 2007. Video footage of the game was also released by Mihara. In the time-limited demo, players had 120 minutes to face off against Doom with a single ship and no bombs. Another demo event took place at Cave Festival in Akihabara on September 23 and 24, 2007. This version has a time limit of 24 hours, and contains extra levels. The retail version of the game was released in Japan in 2008 and includes a DVD Superplay video with the then current world record of the arcade release using Ship A. The game adds the ability to save replays,