MDK is a third-person shooter video game series in which the player must defend Earth from alien invaders. There are two games in the series; MDK, released in 1997, and MDK2, released in 2000. MDK was developed by Shiny Entertainment for Windows, and ported to Mac OS by Shokwave and to PlayStation by Neversoft. It was published on all systems by PIE in North America and by Interplay Entertainment in Europe. MDK2 was developed by BioWare for Dreamcast, Windows, PlayStation 2 and Wii. A HD re-mastered version, developed by Overhaul Games was released for Windows in 2011 as MDK2 HD. MDK2 was published on all systems by Interplay.