>>111301553Since is out already.
Jason was absolutely supposed to be Leviathan, so much that in fact hijacked Lobdell's plans for the Outlaw.
Prince of Gotham was an arc written after Bendis decided to make Jason Leviathan and was supposed to explain how in the fuck Jason managed to become a James Bond villain overnight. The gist of it is that he would use Penguin's resources to slowly take over criminal groups all over the world and then use those resources to take down the DCU spy agencies. His motivation would be revenge over Roy's death, ensure no one else would die like that because heroes fucked up.
Then at the last moment Bendis changed his mind, but Prince of Gotham was already happening so Lobdell had to scramble to write off what he could, that's why Prince of Gotham is so uneven and some things happen without reason. Jason's trip to Europe was supposed to start the takeover, Essence's reason to fight Jason was her knowing he was Leviathan and what he was planning. That's why Leviathan randomly appears in issue 35.