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Excerpt:

 In this article, I'll explain how to make a multiplayer map from scratch and then tell you how to improve it. At the end of the article we'll take a look at different gamemodes/layouts and how they might affect the levels design. As usual, I tried to write this article in an interesting fashion and added a lot of pictures and illustrations. Please don't be lazy and skip the examples, because I explain some important concepts in them. When I talk about players and teams I assume they all have similar skills and experience. It's not down to luck that hard-core gamers usually win against noobs, but in a balanced teammatch if one side consistently wins it might be because the leveldesign is bad and that is what I want to talk about.