I was looking around and finally found what I was looking for, Attack on Titan, the preview for the second season.
If you have not finished watching the first season this part will have a SPOILER ALERT for the last episode of the first season. As you guys remember on the last episode of AoT, Eren is fighting Annie both in Titan form. At first it seems like Eren is losing but ends up overpowering Annie, he then decides to let Annie encase herself in a crystal and admits to this.The military question him of course but he decides to tell them he will not tell them all his plans to prevent leaks. At the end of the episode we see a piece of Wall Sina crumble only to show us part of a titan’s face…
Amazing cliffhanger and have been waiting for what seemed millenniums for this preview.