Earlier in the dungeon, there was a room which the DM described as “Dank”, as in dark and dank. All the players laughed, but he rolled with it and said there was marijuana growing in the room.
Later on, while they were fighting a gelatinous cube:
Barbarian (lowest intelligence character): “Look, you’re stupid, I’m stupid, let’s just sit down and hang out.”
DM: “The gelatinous cube wiggles.”
Barbarian: “I throw an ounce of weed into it”
DM: “Um.. okay, the gelatinous cube wiggles slowly in a relaxed way. Congratulations, you beat my favorite monster by getting it high”