The entity known as the Living Tribunal possesses near-omnipotent powers, the full range and extent of which remain incomprehensible to people of Earth.
The Living Tribunal is a vastly powerful humanoid entity who has existed as long as the universe itself, and whose function is to safeguard the multiverse from an imbalance of mystical forces. Possessing untold power, the Tribunal will act to prevent one of the universes from amassing more concentrated mystical power than any of the others, or upsetting the cosmic balance and threatening the other universes. The Tribunal will also act to prevent a grave imbalance between the mystical forces allied with good and those allied with evil within one universe. Usually the Tribunal leaves matters involving a mystical imbalance affecting only Earth's universe to be monitored by the universe's "abstract" entities Lord Chaos and Master Order, and to be dealt with by their creation, the In-Betweener.
The Tribunal is willing to obliterate an entire inhabited planet to safeguard an entire universe or the multiverse itself, and is fully capable of doing so by an exercise of his own power. One of the most powerful beings in the multiverse, the Tribunal can turn a star into a supernova with a single force bolt.
The Living Tribunal manifests itself as a being with three faces which represent the three sides of the Tribunal's personality. Its front face, through which it usually speaks, stands for equity. The completely hooded face on the right side of its head represents necessity and the half-hooded face on the left side stands for just revenge. All three sides of the Tribunal's mind must be in agreement when judging a case requiring possible action before the Tribunal can intervene.
The Living Tribunal's first known encounter with a being of Earth was with Earth's sorcerer supreme Doctor Strange. He later met the Galadorian space knight Rom and the vastly powerful extradimensional Beyonder.
Living Tribunal's Powers:

The Living Tribunal was created by what some call the Supreme Being. The Living Tribunal seems to be the most supreme being or power in comprehension and has the power to do anything short of its master, whom it calls The One Above All. The Living Tribunal's purpose is to safeguard a number of Multiverses from imbalance and cosmic threat. The Tribunal, like many cosmic beings, uses "manifestation bodies" either of its own creation or from the universe of manifestations so it truly does not have to be at a specific place, but is rather represented. The true form of the Living Tribunal exists everywhere and does not obey the laws of alternate realities.
Text in White represents the original and still unchanged history of the character, while the text in Red represents the new history as changed by The Merge.
White text taken from The Unofficial Handbook to the Marvel Universe. Red text by Michael Sacal.
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