Zombipanda
My Boom-Boom's mostly gay
This is just me throwing some ideas together...
One of Superman's deeds to to defeat the Tyrant Sun. I'm guessing that the Tyrant Sun is either Earth's sun, transformed due to Lex's tampering at the start of the series, or Lex himself, with the powers of Superman. (Parasite did describe Superman's power "like a sun.")
I'd guess it's Solaris, the Living Sun. Didn't he show up in Cadmus Labs?