Where Is the Tiger Guard?

The protagonist Xuanyuan Yi traveled from a peaceful era to a world where supernatural phenomena occur frequently. When he was young, his parents were devoured by sudden phenomena. He grew up in an orphanage. As a strong-boned man, he was not bullied like in his previous life. As the orphanage's force leader, he often calmed down conflicts within the hospital. After the college entrance examination, In order to waive tuition fees, he joined the army and went deep into the Nine Death Lands many times to eliminate mutant aliens. At the age of 27, he became the leader of the second sergeant squad. Because he did not have a higher education, he could not be promoted despite his outstanding military achievements. He temporarily dropped out and resumed school. Later, he was ordered by a senior leader of a certain unit to join a certain unit for half-study and part-time work...