The Knight is seen protecting the Golden Apple. He is the major foe when the squires compete to protect the princess. Little do any of them know that the Mysterious Knight is really King Gregor in disguise.
As it turns out, his most formidable opponent during this competition turns out to be Princess Calla herself, who enters in disguise to avoid being shackled with a protector.
Once Gregor learns the of whole situation, he is deeply impressed at how formidable his daughter has become, and learned to defend herself from those that seek to harm her.