The question "what comes at the end of everything" can have different answers depending on the context. Here are some possible answers based on the search results:

• Riddle answer: The letter "G".

• Scientific answer: The universe will eventually end, and everything that has ever happened, from the tiniest of human kindnesses to the grandest of cosmic explosions, will be gone. The ways in which the universe could end include:

  • The Big Crunch: If the universes expansion were to reverse, the cosmos collapsing inward in a Big Crunch, extremely energetic swells of radiation would ignite the surfaces of stars, exploding them.
  • Heat death: The universes expansion could continue forever, leading to a state known as "heat death" — a barren universe that has reached a uniform temperature throughout. In such a universe, time ceases to have meaning.

Therefore, the answer to "what comes at the end of everything" depends on the context and can be either the letter "G" or the eventual end of the universe.