The Gryphon leader was smarter than the other Gryphons; it understood basic human commands. In case of any danger, even if the four of them could not cope, the Gryphon leader was fully capable of bringing its flock to protect them, or quickly grabbing them and taking the others to safely retreat into the air.
Had it not been for the prior discovery of the stranded whales on the beach, an abnormal phenomenon accompanied by dark, murky waves that led everyone to guess a giant sea monster had appeared nearby, it would have been most appropriate for Knight Isaac to accompany them. Having a human knight accompanying them would make the team look more formal and official.
