Episode 2042 - in which Oscar meets Mr. Snuffleupagus!
https://muppet.fandom.com/wiki/Episode_2042
This is an interesting episode. Gordon plans to wait by Oscar's can to meet Snuffy, Oscar wants him away and tries to trick him, and when Gordon reluctantly leaves for a moment, Snuffy shows up and Oscar sees him. How interesting that the one who believed in him didn't get to see him while the one who did not believe in him (and Oscar mentions to Gordon that he is Big Bird's imaginary friend early in the episode) did get to see him.
I had been wondering if Oscar confirmed to others he was real or if he chose not to (to keep Big Bird angsty), and we see that when he saw Snuffy, he shouted that he was real, though it seems more because he was wanting Gordon to see Snuffy so he would leave. And Gordon thinks he is lying (since he tried to trick him earlier).
It's interesting, until recently, the wiki hadn't really had guides for season 16 episodes where the adults mention their belief, and only one episode where Oscar is shown interacting with Snuffy (I can't wait to see if there are more than two - and there's nearly 50 episodes after this before the season ends). It would have been funny if Oscar ended up being responsible for all of the adults EXCEPT for the ones who blindly believed Big Bird seeing Snuffy. I would be interested to know if there were any season 16 episodes where Big Bird and Oscar bonded over the fact that they have both seen Snuffy (maybe not likely since Caroll performed both, but the two have also had plenty of interactions with each other).
I feel like the scene where Oscar and Grundgetta make a Snuffleupagus costume to fool Gordon should have had Bruno instead of Grundgetta. Might have been a clever way to have them appear to be together without Bruno carryng Oscar's can, though the size difference might be too different for a two-person costume. Though I think the guide says that one got on top of the other - Bruno is a lot bigger than the grouches, so it could have been Bruno holding Oscar's can over him while covered in the costume.
This episode actually looks a little more epic than episode 1966.