The monsters inside were just like they were mentioned. All of them were Basic monsters with levels between 20 to 25. Moreover, they were the same type, Lesser Earth Elemental. They resembled the Small Rock Golem that Jack had fought before in his hunting quest. However, unlike the Small Rock Golem, these Lesser Earth Elementals weren't impervious to physical attacks. Their outer skin was more similar to dirt than rock, hence it was not too difficult to break through their defenses with physical weapons.
Their movements were slow, and they could only execute melee attacks, making them an excellent target for accumulating exp points.
Jack scored more than just exp points. He also got loots from these Lesser Earth Elementals which the cadets ignored. They were mostly coins and materials. There were also trophy items called Elemental Powder which he should be able to exchange for a fair amount of coin in the Hunters Association. He happily stored all the loots.