// ==UserScript==
// @name           facebook.fight.club.autofight
// @namespace      http://altblue.com/
// @description    Fight Club @ Facebook: loony fight ;-)
// @include        http://apps.facebook.com/fight-club/fight.php
// ==/UserScript==

var sb = document.evaluate('.//input[@name="fight"]', document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null);
if (sb) sb = sb.singleNodeValue;

if (sb) {
  sb.click();
} else {
  window.location.href = window.location.href;
}