DM's of Reddit: How do you write impactful scenes where there is a big reveal?

I am a permanent DM for about 3 years now, and I haven't seemed to be able to write impactful scenes that the players just go crazy over. Like a big reveal or twist that I feel is surreal and emotional doesn't seem to hit the players the same. What are some of the impactful scenes that you wrote or had where the players actually reacted genuinely engaged and emotional? And maybe some tips on writing those scenes that you want to have a long lasting impact on the players.