The assassin goblins knew that this was a trap. If the Avatar of Ifrit, Green Fire wanted to finish them in one shot, he would have blasted the tavern to kingdom come. Yet, he did not. It could probably meant two things. One, Green Fire wished to bring in prisoners so that he could interrogate them. Two, he really just wanted to flaunt his powers so much that he could 'toy' with the goblins.
Break them? Burn them? Why not both at the same time? He was after all granted all this power and he did not have any chance to use them until now due to the restraining order by Orc King Hamu himself. Now that his King allowed him to vent some stress, why should he not?
Of course, Ripcaller also believed it was the latter especially since he saw how Green Fire set everything in flames. He deduced that there was a high chance the orc of fire came here alone with no backup. No sane orc would burn the surroundings with his comrades or fellow soldiers beside him…unless they were as crazy as him.