From Halopedia, the Halo wiki
A sardans cat possessed a pair of glowing, bright yellow eyes set into a round face with tufted ears. The cats had long, sleek bodies and flexible tails. They were capable of climbing trees with ease and were known to live in the forests which surrounded the village of Brume-sur-Mer, where they typically stalked through thick, lush overgrowth. These sardans cats were generally terrified of humans and never came into town. The appearance of a sardans cat in Brume-sur-Mer in 2548 struck Evie Rousseau and Victor Gallardo as especially curious.
List of appearances