lesson
Explanation
This is a longer, multi-panel adventure comic that appears to be a parody of fantasy/quest narratives and "lesson-learning" stories. The comic follows what appears to be a group of characters on some kind of journey or quest, with various dramatic events unfolding -- battles, confrontations, and dramatic revelations.
The comic appears to set up an elaborate fantasy scenario with multiple characters going through harrowing experiences, only for the "lesson" to be either completely banal or absurdly disproportionate to the ordeal. The structure parodies children's adventure stories and fantasy epics where characters go through enormous trials to learn simple life lessons.
The humor mechanism is the contrast between the epic scale of the adventure depicted (spanning many panels with dramatic action sequences, explosions, and what appear to be life-or-death situations) and whatever mundane or obvious "lesson" emerges at the end. SMBC frequently uses this format -- elaborate multi-panel setups that build toward an anticlimactic or absurd conclusion -- to satirize narrative conventions and the human tendency to frame experiences as having neat moral takeaways. The sheer length of the comic compared to the typical SMBC strip is itself part of the joke, as the reader invests significant time following the story only to arrive at an underwhelming conclusion.