Assumed to be a millionaire in private life, Max O'Millions is the founding architect and prime founder of the super-hero team known as Honor Guard. He had the insight and the desire to create an organization dedicated to defending humanity, but funded, philanthropically, on a private level.
He has the ability to grow in volume. He uses his giant size to fight crime. Nothing has been told (yet) about how these powers came about, or how long he was active using them in direct conflicts.
- There was an animation series featuring Max during the mid 1970s.
- Circa 1973, and wearing an updated costume, Max may have been involved in defending surface dwellers against Madame Majestrix's Invasion. 
- Kurt Busiek has said that in the imaginary "Astro Comics" line he envisions the Astro City world coming from, Max O'Millions was created in-between the Golden and Silver Ages, during the period superheroes had fallen out of popularity. He had begun as a comic book character in a genre other than superheroes. When the Silver Age hit and made superheroes popular again, he was turned into a superhero. Until and unless there is more information forthcoming, the original comic book genre that this imaginary Max O'Millions likely sourced from is left open for comic book historians of all levels to speculate and debate.
- Based on a facial grimace made by Max, some readers speculate that there might be a bit of friction between him and the Silver Agent. This happened during their first encounter with Shirak. The argument could be that this is the result of their age differences, or a slight envy spawned by a power shift as Max gets shuffled to the background when the Silver Agent takes the spotlight and assumes a strong leadership role within Honor Guard. Putting the entire scene into context, other readers interpret that there isn't any friction in the dialog or the body language of the two characters. They are just practicing solid teamwork.
- Astro City: The Dark Age Book One #4. Page 9.