I love that show, I watch it with my son for sure. I have noticed many references to magic mushrooms and other psychedelics in different scenes. There are always mushrooms randomly around. I love the episode with Quartzion the Crystal Queen, seems for sure to be DMT inspired.

DisEmboDied, I watch show with my kids as well, I don't know who enjoys it more, me or them. Yeah I do, it's me.

There's an episode titled Puhoy where Finn goes to an alternate pillow universe whilst asleep in the pillow fort he and Jake built. He lives an entire life in this universe getting married and having pillow children and growing old and dying. When on his deathbed, right before he dies he says something like "here it comes, oh boy oh boy oh boy!" and when he goes it's really dmt flash-like. Can't find clip on YouTube!
I love the episode referenced by OP, trippy when he puts the glasses on for first time too.

I love this show. Rick and Morty and Regular Show are cool too. Cartoons seem to be getting better. And yeah, it's a psychedelic children's show but I doubt any children, or unpsychedelic adults for that matter, even pick up on any references. They are subtle, and only obvious to people like us, lol.