Looking for a specific Chinese movie (might have no subtitles)

I'm half-Chinese, so I visited some of my relatives in China a few years ago. While I was there, I watched a movie on Youku with my cousin's account. It was about four students who each had an elemental power (fire, water, earth, ???). In the end, they had to combine their powers to defeat the villain. I can't recall the details, but I enjoyed the movie and I want to rewatch it. If you know the title of the movie, please tell me! Thank you in advance!