Hero mansion must be level 10.An oasis has to be within 3 block of your village which has the hero mansion.You need your hero when you try to conquer the oasis and all the natures must be clean out.Hope this help.You can have a look in faq also.
Blizard Senior Member
Number of posts : 165 Age : 64 First Name : Could be Richard In Game Name : _Blizard Registration date : 2008-05-16