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"?>
<api>
  <query-continue>
    <allredirects garcontinue="Facet/pf" />
  </query-continue>
  <query>
    <pages>
      <page ns="0" title="Elemental Plane of Fire" missing="" />
      <page ns="0" title="Ethereal Plane" missing="" />
      <page pageid="1026" ns="0" title="Bloodgem Park" />
      <page pageid="1047" ns="0" title="Chamo" />
      <page pageid="983" ns="0" title="Demiplane of Dread" />
      <page pageid="195" ns="0" title="Djihauti" />
      <page pageid="1120" ns="0" title="Doppelganger" />
      <page pageid="449" ns="0" title="Elemental Plane of Air" />
      <page pageid="1075" ns="0" title="Elemental Plane of Earth" />
      <page pageid="464" ns="0" title="Elemental Plane of Water" />
    </pages>
  </query>
</api>