Dark were originally intended to be released as downloadable content. Game designer Duncan Botwood later clarified that it was unlikely to happen due to technical issues. According to him, "It would have required much groundwork to be laid in the core AI code, which meant that it was unlikely to be available as downloadable content post-release". He also remarked that the Counter-Operative mode was planned during the development of the game, but the idea was ultimately discarded due to the pressure to cut planned content. In May 2006, an auto-update was made available on Xbox Live, responsible for fixing some bugs and adding new multiplayer options to the game. The bug fixes included code to prevent an ongoing problem where players could walk through the air, an issue where some weapons could make use of rapid fire, and a map-exiting glitch, among others. The new multiplayer options provided seven new bot types and the ability to use bots in DarkOps matches, since bots had only one AI variant and were only available in DeathMatch scenarios when the game was released. A playable demo of the game was made freely available on the Xbox Live Marketplace shortly afterwards. The demo included one campaign mission that could be played in solo mode or co-operatively, and a new multiplayer map. A multiplayer map pack, called Perfect Dark Zero Map Pack One, was released on June 7, 2006, containing the demo's new multiplayer map as well as three other new maps to add to the game's original six. Unlike the original maps, the new maps only have one variant instead of two. On October 31, 2006, Rare revealed a special platinum edition of Perfect Dark Zero, featuring the first map pack and two additional maps as extras. The two new maps were later released for free in a pack called Perfect Dark Zero Map Pack Two. These maps are updated versions of the Felicity and Ruins maps from the original Perfect Dark. The pack was released on November 1, 2006 for Gold Members and on November 8, 2006 for Silver Members. Reception Perfect Dark Zero received generally positive reviews from critics. Writing for GameSpot, Greg Kasavin felt that Perfect Dark Zero "champions the Xbox 360 with its excellent assortment of single and multiplayer game types, as well as its incredible good looks and dynamic, intense action". He concluded that the game "delivers just about