<?php
$urls = array("www.website.com/games/RANDOM-URL-TITLE-NOT_NEEDED.xhtml", "www.website.com/games/randomcode1/RANDOM-URL-TITLE-NEEDED.html",
"www.website.com/blabla/randomcode2/RANDOM-URL-TITLE-NEEDED2.htm",
"www.website.com/whatever/randomcode2/RANDOM-URL-TITLE-NEEDED3.html");
print_r(preg_filter
('#^.*/(.*)\.html?$#i', '$1', $urls));
PD9waHAKCiR1cmxzID0gYXJyYXkoInd3dy53ZWJzaXRlLmNvbS9nYW1lcy9SQU5ET00tVVJMLVRJVExFLU5PVF9ORUVERUQueGh0bWwiLAoJInd3dy53ZWJzaXRlLmNvbS9nYW1lcy9yYW5kb21jb2RlMS9SQU5ET00tVVJMLVRJVExFLU5FRURFRC5odG1sIiwKCSJ3d3cud2Vic2l0ZS5jb20vYmxhYmxhL3JhbmRvbWNvZGUyL1JBTkRPTS1VUkwtVElUTEUtTkVFREVEMi5odG0iLAoJInd3dy53ZWJzaXRlLmNvbS93aGF0ZXZlci9yYW5kb21jb2RlMi9SQU5ET00tVVJMLVRJVExFLU5FRURFRDMuaHRtbCIpOwoKcHJpbnRfcihwcmVnX2ZpbHRlcignI14uKi8oLiopXC5odG1sPyQjaScsICckMScsICR1cmxzKSk7