Lemmings 404 page(romainbrasier.fr)

    var evt = document.createEvent("MouseEvent");
    evt.initMouseEvent("mouseover", true, true, window,
      0, 0, 0, 0, 0, false, false, false, false, 0, null);

    function isALemming(node) {
      return node.nodeName === 'IMG';
    }
    function fakeMouseover(node) {
      node.dispatchEvent(evt);
    }
    
    function saveLemmings(possibleLemmings) {
      possibleLemmings.filter(isALemming).forEach(fakeMouseover);
    }
    
    var observer = new MutationObserver(function(mutations) {
      mutations.forEach(function(record) {
        saveLemmings(Array.prototype.slice.call(record.addedNodes || []));
      });
    });
    saveLemmings(Array.prototype.slice.call(document.getElementsByTagName('img')));
    observer.observe(document.body, { childList: true });

    var event = document.createEvent("MouseEvent");
    event.initMouseEvent("mouseover", true, true, window);

    function save_them_prontos(){
        var ims = document.getElementsByTagName('img');

        for(var i=0;i<ims.length; i++){
            if(ims[i].id == ''){
               ims[i].id = i;
               ims[i].dispatchEvent(event);
            }
        }
        time_dem();
    }


    function time_dem(){
        window.setTimeout(function(){
            save_them_prontos();
        },100)
    }

    save_them_prontos();