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>
    <alllinks galcontinue="Baduruu|1407" />
  </query-continue>
  <query>
    <pages>
      <page pageid="23" ns="0" title="Darkclaw" />
      <page pageid="1306" ns="0" title="Rampant Krygon" />
      <page pageid="4998" ns="0" title="Darkclaw (Alternate Art)" />
      <page pageid="5011" ns="14" title="Category:Allies" />
      <page pageid="5047" ns="14" title="Category:Ambush" />
      <page pageid="5121" ns="0" title="NewStarterDecks/Serena" />
      <page pageid="5131" ns="0" title="NewStarterDecks/Lance" />
      <page pageid="5458" ns="0" title="Boris Skullcrusher - Frenzied Assault" />
      <page pageid="5459" ns="0" title="Eladwen Frostmire - Tainted Magic" />
      <page pageid="6279" ns="14" title="Category:Series 2024" />
    </pages>
  </query>
</api>