It is often boasted in "Asterix" that the Gauls fear only one thing: "That the sky will fall on their heads" but I wonder if that is really true?
On page 37 of "Asterix in Switzerland", he and Obelix get on board a boat where they are startled by the loud yodelling of the Helvetians. When they yodel again, Obelix jumps overboard and Asterix orders him to get back on the boat. It would appear as if the most physically powerful of the Gauls can be terrified by loud ear-splitting sounds, like that made by Cacofonix the bard.
I can imagine that Cacofonix's music terrifies people when they hear it for the first time. Take the scene in "Asterix and the Normans" when his singing teaches the Normans the meaning of fear. The Gauls in the village got used to it over time but were still annoyed enough to tie him up and gag him especially during the celebratory feasts.
So the Gauls fear the sky falling on their heads and loud music. Can there be anything else? | 
