Once you do all of Baoba's Safari Zone tasks, you will be the 'owner' of the Safari Zone, and will be allowed to customize it by placing items (up to 30 per area) and changing the land. Placing certain items will allow you to capture certain Pokemon, like if you place 10 peak items (AKA rocks) in a plains area, Houndoom will have a chance to appear. If you leave the items for long enough, they will be worth 2, 3, or 4 times as much. Baoba will call you when they've this happens. This allows you to get some very rare Pokemon: for example, if you leave the maximum 30 peak items in the mountain until they double in value, this will allow you to catch wild Metangs (the pre-evolution to Metagross), which requires a previously impossible 56 peak items placed. Knowing how to double the values of your placed blocks will allow some very rare Pokemon to appear in the wild: Metang, Croagunk, Carnivine, Bronzong, Gible, Trapinch, and even Riolu. Yes, you can even get mini-Lucarios to appear randomly in the Safari Zone if you know how.
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For more information of how the Safari Zone works and how to get the rare Pokemon in it, try this site: they're nearly as good as Psypokes but have different sets of information.
http://bulbapedia.bulbagarden.net/wiki/ ... afari_Zone
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I'm not antisocial, I'm introspective...