It frustrated Berigard extremely to see something that was almost in reach, to be suddenly snatched by someone else. However, he was level-headed enough to know when to press forward and when to retreat.
Never would he have guessed that the mysterious strength of the Lightning Draconic Serpent that he was talking about, was already spent and just like him, it was also running on fumes. But the absurdity of the situation was so great that Berigard did not have necessary information to know that he still had a chance.
Seeing that the orcs were making some peculiar movements, Simon prepared his body to react at any moment. He knew that the mana he had provided to the Lightning Draconic Serpent was completely spent and with that his chances of defeating them had also gone down.
Although he knew it, his days of constantly fighting with monsters had taught him a very important lesson and that was to never show weakness in front of your enemy.