You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information.
<?xml version="1.0"?>
    <images imcontinue="1|Town_portrait_Cove_small.gif" />
      <page pageid="1" ns="0" title="Main Page">
          <im ns="6" title="File:AB.png" />
          <im ns="6" title="File:Artifacts ui icon.png" />
          <im ns="6" title="File:Creatures ui icon.png" />
          <im ns="6" title="File:Heroes ui icon.png" />
          <im ns="6" title="File:Homm3.jpg" />
          <im ns="6" title="File:HotA.png" />
          <im ns="6" title="File:Maps ui icon.png" />
          <im ns="6" title="File:Spells ui icon.png" />
          <im ns="6" title="File:Town portrait Castle small.gif" />
          <im ns="6" title="File:Town portrait Conflux small.gif" />