Not exactly the book mentioned in Thud!, Where's My Cow? uses three distinct art styles. It tells the story of the time (mentioned in Thud!) when Vimes changed the story to a more "city-appropriate" version, removing the animals and putting in city people. The first, most realistic, art style is the real world events. The second, highly simplistic, is for the Where's My Cow? book itself. The third is a cartoony style that anthropomorphises the toys and paintings, a visual description of young Sam's imagination. As young Sam gets more and more worked up the art styles blend together.
Where's My Cow? provides examples of the following tropes:
- Catchphrase: Most of the things Vimes has the Ankh-Morpork characters say are their catchphrases, like Foul Ole Ron's "Buggrit! Millenium hand and shrimp!" or Lord Vetinari's "Don't let me detain you."
- Comic-Book Fantasy Casting: Vimes looks like Pete Postlethwaite in this book, reflecting what was said to be Pratchett's personal Hypothetical Casting.
- Creator Cameo: There's a portrait of Terry Pratchett in Young Sam's room.
- Depending on the Artist: Most characters that were illustrated here were also drawn by Paul Kidby in The Art of Discworld and look rather different in the two books.
- Inherently Funny Words: Both "hippopotamus" and the sound that it's given to make. It goes HRUUGH!
- Please Keep Your Hat On: In possibly the first ever illustration of him sans Watch helmet, Samuel Vimes is revealed to have greasy helmet hair.
- Questioning Title?: Where's My Cow?
- When He Smiles: This is also the first, and probably only, Discworld illustration where Vimes is actually smiling. And not the mirthless, or dangerous, kind he's been known to give just before he cuffs someone, but an actual big goofy, and happy smile.