<table>
    <caption>Superheros and sidekicks</caption>
    <colgroup>
        <col>
        <col span="2" class="batman">
        <col span="2" class="flash">
    </colgroup>
    <tr>
        <td> </td>
        <th scope="col">Batman</th>
        <th scope="col">Robin</th>
        <th scope="col">The Flash</th>
        <th scope="col">Kid Flash</th>
    </tr>
    <tr>
        <th scope="row">Skill</th>
        <td>Smarts</td>
        <td>Dex, acrobat</td>
        <td>Super speed</td>
        <td>Super speed</td>
    </tr>
    <tr>
        <th scope="row">Weapon</th>
        <td>Martial, gadgets</td>
        <td>Martial, gadgets</td>
        <td>Martial</td>
        <td>Martial</td>
    </tr>
</table>

Output