function escape(s) {//escapes a regex, from 3561493

    return s.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');

}

​

var array = [

"<b>Test</b>",

"of the <div style=\"color:red\">battle</div> system"

];

​

var cElem = document.createElement("span");

​

var cleanArray = array.map(function(elem){

   cElem.innerHTML =  elem;

   return cElem.textContent;

});

​

var s = "Test"

​

for(var i=0;i<array.length;i++){

  var idx;

  while((idx = s.indexOf(cleanArray[i],idx)) > -1){

     s = s.replace(cleanArray[i],array[i]);

     idx +=(array[i].length - cleanArray[i].length) +1;//update the index

  }

}

alert(s);

document.write(s);