The climactic scene in &ldquo;Ong Bak 2: The Beginning,&rdquo; a fierce battle between the put-upon Tien (played by actor/director Tony Jaa) and an ever-expanding hive of willing yet incompetent ninjas, is such a brutal and beautiful explosion of choreography and kung-fu craziness that it qualifies as one of the best martial-arts fight scenes ever. 