== NPOV == 

 This sentence sounds a little biased: 

 "Adventure Island is considered by many as a slightly depraved version of Wonder Boy but still managed to sell more copies than its SMS counterpart due to the lack of popularity of the Sega Master System in North America and Japan." 
 If a reliable source can be cited that says that "Adventure Island is considered by many" to be of lesser quality than Wonder Boy, I'm fine with that.  But it seems to me like this statement was simply fabricated by one of the editors of this article.  If a source can be cited, cool.  But if there can't be, I say either the sentence be deleted or stated in a more NPOV.