ALL BATS MADE FOR WINDOWS 8 MAYBE SOME DONT WORK RIGHT YOU JUST HAVE TO SEARCH ON GOOGLE !
Iam Using updated Rathena with an older item and mob db because of customiziation ( will update it soon see Seetingup Server) and 2013.08.07 exe with rms full client!
Anotherway like the Prefix add batch would be the Windoes Function look here: http://www.howtogeek.com/111859/how-to-batch-rename-files-in-windows-4-ways-to-rename-multiple-files/