There is a secret egg (looks like Saphira's egg) on each level (including the Saphira and Eragon levels), which unlock a video about an aspect of the game. Eggs do not need to be collected in order, though the videos will be made available in the same sequence each time.
Once all the eggs have been collected, a Survivor type level is unlocked, where Eragon and Murtagh are in the Throne Room, and fend off never-ending waves of enemies until the player gets tired of playing or one of the characters succumb to the enemies.
No cheats have been found for this game. The only "cheats" found so far are unlockables.
there are tons of unlockables
There are secret unlockables for SVR 08 but only in the UK.
i haven't found any unlockables yet.
Eragon
Ed Speleers played Eragon in the movie.
In Eragon the dragon is called Saphira and her rider is Eragon
Eragon does not have a religion.
Ed Speleers played the character of Eragon in the movie adaptation of the book "Eragon."
Characters: Eragon, Roran (Eragon's cousin), Arya (elf who got the egg to Eragon) Saphira (Eragon's dragon) Brom (storyteller/dragon rider/Eragon's dad), and galbatorix (main antagonist).
Eragon
Book one in the Inheritance Series is called Eragon. The only known riders in Eragon are Galbatorix and Eragon himself, though at the end of Brom's life Eragon learns that he too was once a rider.