Eragon defeated the Shade in a swordfight between them. The Shade almost won because Eragon fell when the Shadecut his back with a sword. But the Arya smashed the rose saphire, and it fell on Durza.
Robert Carlyle
Demonic spirits
Arya used her magic to create a bright light that momentarily blinded Durza and distracted him, giving Eragon the opportunity to stab him with his sword Zar'roc. This allowed them to defeat the Shade and bring an end to his evil influence.
In the film adaptation of "Eragon," the character Shade is portrayed by actor Robert Carlyle. Shade is a significant antagonist in the story, known for his cunning and magical abilities. Carlyle's performance adds depth to the character, making him a memorable part of the film.
It seems that, yes, he was the only one during his existence. However, in the last book, Brisingr, at the battle of Feinster, the three magicians create another shade, which is killed by Arya and Eragon.
The main ones are the Ra-zac, the Shade Durza, and Galbatorix.
Brom is only alive for a period of time in the first book, Eragon. He passes away after a fatal wound from the Shade he and Eragon fought. Eragon and Saphira built a tomb for him atop a mountain.
To avoid spoilers, I won't reveal the outcome. However, the fourth book in the series, "Inheritance," centers around Eragon's journey to defeat Galbatorix, the evil king. The book explores Eragon's growth and struggles as he faces off against the powerful ruler.
Brisingr, the third book in the Inheritance Cycle by Christopher Paolini, sees the protagonist, Eragon, continue his quest to defeat the ruthless king, Galbatorix. The resolution involves a final battle between Eragon and Galbatorix, during which Eragon discovers a way to defeat the king using his true name and the Eldunarí. After a fierce confrontation, Eragon emerges victorious, bringing an end to Galbatorix's tyrannical rule.
In the book Eragon, the conflict was resolved through a final battle between Eragon and Galbatorix, the main antagonist. Eragon was ultimately able to defeat Galbatorix by using cunning strategy and exploiting a vulnerability. After Galbatorix's defeat, peace was restored to the land and Eragon played a key role in rebuilding and establishing a new order.
In the prologue, Arya is captured by the shade Durza. In the following chapter Eragon finds a mysterious stone when out hunting and takes it home to the farm where he lives with his uncle and cousin.
Of all that we know so far, the Menoa tree knows eragon wants to kill Galbatorix, so like he other woman who made Eragon's new sword Brisingr, she takes the fact in Eragon will defeat Galbatorix.