Simplify the following text for a Grade 7 native English-speaking person.
Original: Once there , Eragon meets Oromis and his dragon Glaedr , the only dragon and Rider secretly alive besides Eragon , Saphira and Galbatorix .
Simplified: Here he finds out that the mysterious Mourning Sage had been another rider named Oromis , and his dragon Glaedr . Oromis is an Elf and is very old so he can not fight Galbatorix but he can teach Eragon and Saphira .