treadmill
Explanation
The Joke
A knight confronts a dragon, demanding that it give back the princess and surrender all the destiny crystals and its soul to "the word." The dragon, instead of fighting, offers practical life advice: "Sure, at first you'll be happy. You've enslaved a human and you've got some shiny objects. But it's like a hedonic treadmill. You'll cast a dread shadow over all the dragonland, but then what?" The dragon continues: "You'll just be in a steady disposition. You'll get bored, then sad, then anxious, then self-loathing."
The final panel, labeled "Decades Later," shows the knight on a therapist's couch saying, "I should've run away when I was 18 to be a philosophy major in college instead of enslaving the universe." The joke is that the dragon's philosophical warning about the hedonic treadmill was completely correct, and the knight -- having achieved everything he set out to do -- is now miserable and in therapy.
The Humor
The comic subverts the classic fantasy quest narrative by having the dragon deliver genuinely sound psychological advice about the "hedonic treadmill" -- the well-documented phenomenon where people return to a baseline level of happiness regardless of major positive or negative life changes. Instead of a climactic battle, the dragon essentially gives the knight a therapy session, warning that conquering the world will not bring lasting satisfaction. The decades-later payoff confirms the dragon was right all along, and the knight's regret about not studying philosophy is the perfect ironic twist: he could have learned about the hedonic treadmill in a classroom instead of discovering it the hard way through world domination.
References
The "hedonic treadmill" (also called hedonic adaptation) is a psychological concept first described by Brickman and Campbell in 1971, which posits that people tend to return to a relatively stable level of happiness despite major positive or negative life events. It is a foundational concept in the study of subjective well-being and is frequently discussed in philosophy and psychology courses.