User blog comment:Shadow001/Revelation/@comment-1948423-20111015163458/@comment-3465526-20111015232543

Presumably the scar came before the meteor, but we'd need more basic history on Earth-16 (we don't even KNOW he's immortal)

Greg said in interviews that they had a 16 member JL, Guy was there at the end of the first episode and I think Plastic man was too (would need to check), but presumably the other heroes were not League members, just helping out.