They're also valuable. "Unicorn products are worth four times as much as domestic animals, making unicorn genocide in the name of profit an attractive proposit

They're also valuable. "Unicorn products are worth four times as much as domestic animals, making unicorn genocide in the name of profit an attractive proposition." - DF Wiki http://dwarffortresswiki.org/index.php/DF2014:Unicorn http://dwarffortresswiki.org/index.php/DF2014:Unicorn