Landines (or Guardforms) were specially modified and trained to be guard animals. They were genetically modified from wild creatures and trained to protect their owners at any cost. They were polymorphic, but stayed in one specific form.
The Landine who was with the Annarenes on Earth took the form of a small black dog with blue eyes. After they were killed, the Landine was passed along to Countess Gallowglass and stayed in the form of a cat. (PROSE: Relative Dementias)