You need to work on two things- your organization and your grammar/proof reading skills. A good example of this is in the second paragraph-

"The plot of the Mario series is fairly consistent, but it does vary from game to game. However, usually it involves Mario, Luigi (who is Mario’s younger brother) and some of their friends and allies (such as the various colored Toads, Yoshi, etc.) on their question to rescue Princess Peach from the Bowser and his army of Koopa Troopas."

Organization here is disjointed in two ways- the first and second sentences restate information in a rather cumbersome way, and the paragraph introduces a large number of story components without explaining them at all, which given the nature of this article (for people who've never played or heard of Mario?) should certainly be a priority. Meanwhile, you have Mario and his friends going on a "Question" to find the princess. I'm not sure what they plan to ask Bowser to get her back, but I'm sure it'll be thrilling beyond belief.