It is mentioned in the Silver Chair that Eustace is afraid of heights, causing him to overreact when Jill goes too close to the edge of a cliff.

In other respects, Eustace displays great courage and a fair degree of discernment in facing the challenges that confront him in the Narnian world.

Much of the narrative of The Voyage of the Dawn Treader concerns the personal growth of Eustace, as he is drawn into Narnia and aboard the eponymous ship along with Lucy and Edmund, and into adventures that bring him to realize how self-centred his attitudes are.

He describes the ship sailing in perpetual storm (though the weather is fine), and portrays the others as foolishly denying the supposed rough seas and refusing to face the "truth" of the situation.

He complains when Lucy is given Caspian's cabin, and comments to the crew that giving girls special treatment is actually "putting them down, and making them weaker".

Being a dragon changes Eustace; instead of behaving like his usual sulky self, he helps the travellers find food, shelter, and a tree to serve as a new mainmast.

Eventually, Eustace meets Aslan, who returns him to human form by peeling off his dragon skin and sending him into a refreshing bath.

The two journey to the far north of Narnia, and the world below it, to recover the lost heir to the throne and to thwart the plan of the Lady of the Green Kirtle to overthrow the kingdom.

Meanwhile, a railway accident in England has resulted in the death of Eustace and Jill, along with Lucy, Edmund, and Peter, as well as Polly and Digory.

Writer Philip Hensher objected to the description of Eustace and his family, regarding it as evidence of supposed anti-intellectual and anti-progressive leanings.

Similarly, he was not against progress in the sense of objectively justifiable social improvement, but did oppose purely fashionable progressivism, and in particular what he called "chronological snobbery", the view that the superiority of modern values can always be assumed automatically and without investigation.

The Oh Hellos, a folk rock band, wrote a song "The Lament of Eustace Scrubb" on their 2012 album Through the Deep, Dark Valley.