The giant black bird that descended from the sky was a native of this particular dimension. The academy staff had tamed a few and their role was to be a hindrance to the students.
This was the first obstacle that students faced if they didn't pass a certain point within a given time. To clear this obstacle, one needed to cross the checkpoint within a given time or harm the bird until it got killed or escaped. The bird was trained to run away as soon as it felt a certain level of damage so the capture students' only way out was to fight it.
The students, being in awe of the toppers' prowess, halted and wasted their time, thereby getting attacked by the bird. The bird captured four more students and the rest flew away in the meantime. The five captured students felt fear but tried to fight the bird and be freed from its clutches.
Lith, Ralph and Dennis had crossed the checkpoint in time due to speeding up earlier and avoided the bird's attack.
