Upon the fireball being blocked by another earth wall, the pressure made a hole in it, and Yue dashed through, before they could notice that is. As they looked for him on the field before them, he started silently killing those at the back of the regiment. Slicing their throats. He killed 4 before they noticed and turned and tried to reposition themselves to deal with their enemy on both sides.
Although this regiment only had to fight one enemy on the one side, he was clearly skilled enough to take out a few of them before they even noticed, and got past them.
As they were repositioning themselves, Yue before continuing his assult on these troops, looked up and saw the next volley of the ballista arrows, and trebuchets heading his way. He even saw a few spells, and decided to run in the opposite direction temporarily. As he ran, he looked back occasionally to see if they were following him.