Basically this match-up pits a video game character with potentially limitless power, up against what amounts to essentially Christopher Paolini's power fantasy, not dissing the Inheritance Cycle but just being realistic. In the books we see Eragon progress from being a farm boy who needs Saphira's help to do basically anything, into basically a demigod who can turn mortal men into mist, and with Saphira and the Eldunarí can basically butt-rape anything in Paolini's universe neatly. This is not so much an issue of specific character abilities or traits, and much more an issue of scaling of power.