Complex sentence: When Seth and Eirika are outside the castle they are met by Valter a Wyvern General of Grado, in order to protect the princess Seth attacks Valter but gets injured, just as the battle begins, Seth grabs Eirika and they run away headed to Freila.
Split into simpler sentences: When Seth and Eirika are outside the castle, they are met by Valter, a Wyvern General of Grado. Just as the battle begins, Seth grabs Eirika and they run away headed to Freila.