Trotsky has the wrong end of the stick:
> Eh? I thought that familiars could only be incomplete creatures or
>inanimate objects, and a herd-man is neither. Mind you, I always thought it
>was a bit of a pity you couldn't have a black cat as a familiar or something
>like that. Have I misread the rules or has Tal? Or is there some way of
>making a familiar I've forgotten about?
A goat can be a familiar, according to RQ3. It has a fixed INT and is
therefore incomplete. So has a herd-man and a cat of any colour.