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Probotector is an alternate title originally given to a number of different Contra franchise video games in the European and PAL regions.
Their main difference is that the human protagonists of the original games were substituted with generic robot soldiers to avoid the exposure of young gamers to depictions of violence between human beings.
By itself, the title was affixed to several different Contra games, and may refer to the European localizations of Contra, Super Contra, Operation C, Contra III The Alien Wars and Contra Hard Corps.
The original Probotector robot also appeared in the Contra Dual Spirits Nintendo DS portable game from 2008 as a bonus playable character.