Though the flames couldn't harm him, Gregor jumped back in shock when they were blasted back at him, cutting off his fire breath attack. The reflected flames washed over him like a tide of water, melting the snow around his feet, but he was left unharmed. When the fire cleared and he gained sight of the cave again, the entrance was sealed and an angry caveman was hacking away at the opening. Unsure about who summoned the obstruction, Gregor hesitated for a moment. He didn't dare approach, lest he be singled out against such a powerful opponent. Besides, he had no idea whose side the crazed caveman was on, if anyone's. So instead, he filled his jaws with fresh fire and held it there, forming it into a fireball. If the wall of spikes was Adrian's, it would give him time to charge a more powerful attack until Arthur emerged again. If it was somehow Arthur's, he could use the fireball to blow it up, or at least try. For now he just charged.