Light's group had arrived before the Sith and the two members of the group who seemed to accompany him. The problem with having numbers in a battle is that you tend to reduce the effectiveness of yourself and others. When Avriela and Varik arrived, Light ran over to where Zarev was, now on the ground. He took up a position between Voleran and Zarev, trying to figure out Zarev's condition and protect them both at the same time. To this end he had drawn his lightsabers and gone in to a defensive stance, though he cast a glance at Zarev and asked, "Are you okay? Can you fight?"
While he did, the showy Sith was having a grand time making his entrance and announcing his allegiance. Light only paid enough attention to note that he was going to fight Voleran and he looked at Varik with a raised eyebrow, curious about how this particular turn of events had occurred. After that look though, his focus returned to Voleran and the Sith, wanting to see if they would fight.