The Living Tribunal may or may not have been defeated when
Thanos claimed the power of
Heart of the Universe for himself, and seemingly absorbed the Living Tribunal, along with
Eternity, and
Infinity. However, given that Thanos only absorbed and recreated a single universe, whereas the rest of the multiverse suffered no effects from his actions, it was likely just a
Manifestation Body/weak avatar of the Tribunal.
[
This interpretation was validated by Marvel's executive editor
Tom Brevoort, who stated that like all, "
The End" series, the story was intended to have no effect whatsoever on continuity, and if it had, Death would have been made absolute again, which it was not. So the entire event may also have taken place as an "imaginary story" completely outside of Marvel's multiversal continuity.
This is what the marvel wiki says (i know the marvel wiki might not be accurate but it was validated by him)
people here don't trust tom. (i've said
it before but they didn't believe me)
do you think i'm right about the heart of the universe?
btw is that america chavez as your profile pic