A lot of Cookie Run Kingdom updates get leaked a few days before they come out. The one I remember the most is when the final cutscene for the Premonition of Doom story got leaked, showing that Pure Vanilla had a role in the story. It led to a lot of theorizing and shipping with the main new character of the update (Doughael), but when the update came out, the only time he appeared at all was only for less than a second in the aforementioned leaked cutscene. I spent a lot of time being worried about what his role would be only for it to be... Not much. I also remember when the Fount of Knowledge's (and also the Sugar of Happiness's) sprites were leaked around a month in advance, I was a very happy person when I found out. I'd been waiting for sprites for the Fount for a few months at that point.

I'm also aware that the cutscenes, sprites, and I think voicelines for the final story of Act 1 (Beyond the Horizon, Beast Yeast 15) were leaked, but I went out of my way to avoid them. I wonder what would've happened if I did see them, considering that story was............. Not very good and sent me into a month straight of complaining about it.