"Even eternal darkness can be dispelled with a single light."
Millions of years ago, Epsilon Invictus served as the captain of an Autobot space cruiser. At the height of the Autobot-Decepticon war, Invictus' ship took part in a massive fleet battle at the outer edge of known space. Both fleets were annihilated when they strayed across the path of... Unicron! Epsilon Invictus was the sole survivor of the encounter, but he was barely functional and he'd been blinded by the mere sight of the then-unknown horror. Broken and battered, his spark nearly extinguished, he drifted through space until he was salvaged and repaired by a friendly race. For millions of years he traveled from world to world searching for Cybertron. He was desperate to warn his planet of the nightmarish Unicron -- the last sight he had ever seen.
Epsilon Invictus transforms into an aerospace cruiser. While most of his weaponry is still functional, his blindness has limited it's effectiveness. He has, however, mastered the Energon blade -- a difficult weapon made of pure energy -- and wields it with deadly precision in close combat despite his blindness. The storied blind swordsman always seems to have one more Energon Blade technique in his memory banks no matter how hard a foe presses him.
Once a proud and headstrong Captain of the Autobot fleet, Invictus' nigh-endless travels have made him more patient and more accepting of the opinions of others (though he's still rather stern). He has traveled to thousands of worlds, always doing what he could to help people live freely and peacefully, as is the Autobot way. Many worlds share legends of great metal guardian who delivered them from evil.