<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
    targetNamespace="urn:example"
    xmlns:bt="urn:example">

<xs:element name="Easy" type="bt:EasyChoice"/>
<xs:element name="Hard" type="bt:HardChoice"/>

<xs:complexType name="EasyChoice">
  <xs:choice>
    <xs:element name="name" type="xs:string"/>
    <xs:element name="rank" type="xs:int"/>
    <xs:element name="any"/>
  </xs:choice>
</xs:complexType>  

<xs:complexType name="HardChoice">
  <xs:choice maxOccurs="unbounded">
    <xs:element name="name" type="xs:string"/>
    <xs:element name="rank" type="xs:int"/>
    <xs:element name="any"/>
  </xs:choice>
</xs:complexType>  

</xs:schema>
