Seraphina's body was sticking to Viktor's body as he shielded her in case Verona's barrier gave away.
But surprisingly or not, Verona's flame barrier was deflecting away all the spears and knives that some goblins were throwing in their direction.
And even though Pobi and Pubo looked dumb, they surely knew how to effectively use their bow and arrow, evident by how they were sometimes killing two goblins at once with just a single arrow.
Viktor noticed that these arrows weren't simply shooting out from pure physical force, but they seemed to carry much more speed and strength with a faint gray aura covering them.
Based on what Seraphina had told him before, these twins must be practicing and using some kind of arts that used the element of 'Air' to increase their attack power.