Alexander was not going to make the same mistake twice in such a short time. The first time might have been due to his lack of anticipation, but now that he was aware, he wasn't about to fall for the same trick again.
Throughout the entire time he was fighting this group of students, his guard was always up. He may have appeared relaxed and easygoing at a glance, but his senses never relaxed.
Whoever the archer was, he or she was bound to come after him again. Even if that person were not, there were bound to be others.
When he picked up a faint whistle of something travelling through the air, Alex did not need to think twice and evaded the arrow that zoomed past his head a second time.
However, unlike the previous one, this one continued on its path and struck a student directly in front of Alex, taking him out.