Warning: contains spoilers for Justice League #75!
The entire Black Adam, is not who many would many would call a heroic sort - and that makes him the perfect survivor.
DC had previously announced the entire team would die as a prelude to the mysterious Dark Crisis event, and the latest issue did not disappoint on that end. The of the most powerful team on the planet are summoned from different corners of the Earth (and in some cases, from space) and collectively transported to the Hall of Heroes, the headquarters of the Justice League Incarnate. There, they are met by President Superman, who warns them of a dire threat: the Great Darkness has returned and threatens the entire DC Multiverse.
The Justice League are suddenly transported to the ruins of a nearly-destroyed Multiverse where they come across the villain Pariah. Pariah is unfortunately affected by the Great Darkness, saying the Great Darkness only desires peace, not destruction - but in order to rebuild the multiverse, the universe of the Justice League must be destroyed. Pariah attacks with the Dark Army, a collection of the League's most fearsome villains, all of which are enthralled by the Great Darkness. Using the Great Darkness' power, Pariah easily kills Superman, Batman, Wonder Woman and the entire Justice League in seconds save one person: Black Adam. Black Adam transports to safety just before he too is destroyed. "They're all dead," he says upon his return. "The Justice League...are dead."
Black Adam is not a villain, but he's not entirely a hero either. One of Captain Marvel's (now better known as Shazam) earliest foes, Black Adam is thousands of years old and powered by powerful magic. He is perhaps the Marvel equivalent of Namor the Sub-Mariner, if not in powers then in personality and place within the DC Universe. He is more ruthless than the other of the Justice League, and certainly does not inspire others like Superman or Wonder Woman.
Is it these aspects that make Black Adam a perfect survivor. With the Justice League dead, he is now the only remaining member, but he is perhaps the least "heroic" of them all. He was already an outlier among the Justice League, but now as the only member, Black Adam must lead the charge against the Great Darkness - and bring back the heroes who died fighting it.
