Border Down is a horizontally scrolling shooter video game developed and published by G.rev. It was released in Japanese arcades in April 2003 on Sega NAOMI hardware, and was ported to the Dreamcast later that year. The story takes place in the future where humans are defending their Mars colony from an invading alien attack. The game employs a "border system" where each stage has three variations of different difficulty. The player starts on the easiest variation, and is lowered to a more difficult variation with each subsequent loss of a life.
Producer Hiroyuki Maruyama was heavily inspired by Taito's shooter Metal Black (1991) and founded G.rev with ex-Taito employees specifically to develop a shooter of his own. The team of five did subcontract work to gather funding and build their skills programming NAOMI arcade hardware. Among the projects they worked on were Treasure's Ikaruga (2001) and Gradius V (2004). Due to lack of funds, they were not able to realize all the ideas they conceptualized for the game. Border Down was released to mixed reception, but was commercially successful and continues to maintain a steady interest from shooter fans. G.rev went on to make other shoot 'em ups including Senko no Ronde and Under Defeat.
Gameplay
thumb|left|The player, controlling the red ship, fights off enemies to the right in the first stage.
Border Down is a side-scrolling shoot 'em up set in a futuristic setting. The game's name is derived from its "border system".
The initial concept for Border Down took root with Maruyama before he founded G.rev. He was heavily inspired by Taito's shooter Metal Black (1991), specifically the game's "Beam Level" system. The music was composed by Yasuhisa Watanabe, who also composed the music to Metal Black and was the only member of the staff who had worked on the 1991 shooter.
Release
Border Down was released in Japanese arcades on 25 April 2003. It was common for NAOMI shooters to be ported to Sega's home console, the Dreamcast, making a significant portion of the aging console's extended output. If bought through Sega Direct, the game came with a Border Down branded mouse pad. In addition to the standard version, 3000 limited edition copies were produced that came bundled with the soundtrack. Maruyama was prepared to fold G.rev if Border Down was not successful, but the number of customer orders at launch exceeded G.rev and Sega's expectations, so they continued producing new copies until they felt demand was met. By 2007, Japanese retailer Messe Sanoh was still seeing demand for the game, and so requested Sega and G.rev for another production run. Their request was granted; a second run was produced and sold exclusively through Messe Sanoh retailers beginning on 17 January 2008. Both production runs included, less than 20,000 copies were sold. In 2011, Maruyama said that he would consider rereleasing Border Down or his 2005 game Under Defeat on modern platforms. Under Defeat was rereleased in 2012 for the PlayStation 3 and Xbox 360. A resin kit for the player ship from Border Down was released in February 2013.
Reception
Initial reactions to the arcade release were mixed. Maruyama recalled: "It's a really individualistic type of game, so when we first released it [in the arcades] it received both positive and negative reactions". Jeuxvideo.com believed it to be the best horizontal shooter for the Dreamcast. Kalata and Jeuxvideo.com agreed that the game had excellent replayability due to the border and scoring systems.