From the moment they had been dropped from the sky, Flynn who instead of looking downwards and figuring out a way to safely land onto the arena, had instead decided to glance back upwards out of sheer curiosity of how the dark space worked.
The green aquamarine-eyed youth had then noticed that the black rectangular structure had almost immediately began taking form again slowly, almost as if the academy had plans to put something or someone in there again.
Following this odd phenomenon that he had noticed, he had been glancing up at different intervals despite having to battle all manners of robotic beasts but at some point, he realized that it was inefficient for him if he had to keep glancing upwards at intervals.
That was why he had gradually moved around the arena till he found a good elevated point (case in point, the small hill) that would make it easier for him to keep track of what was going on in the black floating box easily while still battling the monsters.