Most of the City of Trial's inhabitants could only be described as weird. They were willing to separate a shard of their soul and seal it into a place where time passed hundreds of times slower than everywhere else.
There was not much to do in the City of Trial, except wait for the Fate Changers to train them. That was the mission they had been given by the Universe.
However, the goal the Soul Shards had in mind was not always, or almost never, the same as the Universe's will. While some Soul Shards wanted to learn more about themselves, and comprehend the deepest levels of the techniques they had created on their own or had been taught by someone before waiting for the opportunity to leave the City of Trials, there were also Soul Shards who never intended to leave the City of Trials.