Not the only Big Dog
Jace was not the only player who had found a way to cheat the system, however, he was the only one who was cheating the system on a significant scale repeatedly without having a hidden class to support him.
Unique classes in Terra Nova, although as rare as a Phoenix's feather, did exist, and not every unique class had the opportunity to be involved with the gameplay from day one.
Some hidden class players like Eren had to wait till the Demon War started for their hidden class to trigger, while some were still waiting for their moment to shine.
Whether it was through a lack of opportunities, or a lack of converting given opportunities into success, not every hidden class player was as successful as Leo, however, every unique class player was more or less more successful than the average player in the world of Terra Nova.
One such unique class player who was waiting for his moment to shine was a player called 'Big Dawg'.