@Kusimanse the story;
a while back I was thumbing a game supplement of Underdark PCs, including a suggestion of how to play derro insanity. I thought it might be fun to have a character whose valuation of treasure is purely internal and is likely to collect prize loot, stuff which would be fantastic for other character classes, and complete garbage. So to this brave PC the fish nailed to his shield is a powerful magical talisman.
@Leucrotta A nifty idea indeed! I was curious about it. :)
@Leucrotta Having a fish on your shield does not make it Scale Armor