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>
    <alltransclusions gatcontinue="Character|1813" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1756" ns="0" title="Liam Ambareth" />
      <page pageid="1788" ns="0" title="Alfhild Fjolvirsdottir" />
      <page pageid="1790" ns="0" title="Kadim ben Hazred" />
      <page pageid="1797" ns="0" title="Constantin Ewan Alastair" />
      <page pageid="1801" ns="0" title="Viola Tania" />
      <page pageid="1803" ns="0" title="Athyr Abu-Aishah" />
      <page pageid="1805" ns="0" title="Alvar Hallvardsson" />
      <page pageid="1809" ns="0" title="Falkenauge" />
      <page pageid="1810" ns="0" title="Charakterseite" />
      <page pageid="1811" ns="0" title="Elcaran Pyriander Belizeth" />
    </pages>
  </query>
</api>