- "At just that moment I saw, far behind me, a huge, dark red, almost purple hump above the water. It seemed to be covered with hundreds of small fish tails, all beating frantically. [...] A huge purple-and-red mottled bag that undulated and oozed through the water. It was propelled by the three huge water sacs, firing one after another. Between those loud bursts, the hundreds of tiny tails that covered its entire surface thrashed and kept up momentum."
A Mardrut is an oceanic creature that lives in the oceans of one of the moons of the Andalite homeworld. It is the size of a whale with dark red skin and hundreds of little thrashing 'fish tails' to keep up momentum. It moves by shooting water out of three massive water sacs attached to its underside. Though it isn't terribly fast, it does not easily tire, although it cannot maneuver well. Visser Three morphs this creature in The Message.