It is the end?

Night came by and the cadets were gathered to take their dinner. "We are done here" One cadet whispered as he ate his food on the bowl as he munched on his food, he would look at the other cadet with him. Then one cadet replied to him "I think so, we are destined to defend this and we already did our best and those barbarians would be no match against our technology which gave us an upper hand in this battle".

 then the other cadets would agree on what the other cadet said "Yeah I think we are to fight those Barbarians with our guns that can pierce them through their flesh" then the cadet laughed. Then after a few minutes, another drumbeat would be heard at the walls. "What's that sound, it seems like a drumbeat? Is it? Hey, Karl checks it out" then the cadet named Karl would try to peek at the wall and would see 500 Barbarians charing at the walls.