A donkey legionary
Imagine a perfectly aligned battalion of Roman legionaries, standing straight as trees and holding their carefully sharpened pilum. Now, add a complete fool, with a half-witted smile, drawn by Albert Uderzo slightly out of line with this neat regiment, as if to show how long it took his superior's command to reach his brain and for him to understand the order to stop.
This idiot is Cadaverus! An here he is, in the finest Roman tradition, designated as a «volunteer» by his decurion to serve as a guinea pig for Valueaddedtax and Getafix, who must prove that they are real druids in order to obtain permission to travel to the forest of the Carnutes, where the Order of Druids is holding its prestigious annual meeting.
Cadaverus follows orders, and chews some of the herbs prepared by Valueaddedtax, the Belgian druid. The result is astonishing, because poor Cadaverus suddenly starts braying! This comes as a bit of a surprise, although not to his decurion, who declares «it hasn't made that much difference»!
In which book ?
3 - Asterix and the Goths