Turtaqua are hatched. When they emerge from the egg, they weigh sixty to seventy-five pounds and are size Small, have 1+4 HD, AC 7, and a movement rate of 10'.
Turtaqua reach adolescence in three years, at which time they weigh 175 to 225 pounds, are size Medium, have 5+4 HD, AC 5, and have movement 15'.
Adulthood is reached at five years, at which time Turtaqua are Large creatures weighing 400 to 500 pounds, have 6+ HD, AC 4, and a movement rate of 20'.
Turtaqua can assume a bipedal humanoid shape very reminiscent of the Tortle race once daily for up to five minutes per HD or level. While in this form, they weigh only 60% their normal weight and gain an addition 5' movement per round. If this time period elapses and the Turtaqua doesn't have room to resume its usual shape, it suffers 1d4 HP injury and gains a level of exhaustion. This continues once every 12 hours until the turtaqua can revert, or until it dies.
Turtaqua can breathe water, remaining submerged for hours. They prefer freshwater but can survive in bogs, fens, and saltwater. When swimming, they gain +10' movement.
Every third round of combat (3, 6, etc.), a Turtaqua may opt to charge and trample. They must move in a straight line at least fifteen feet and attack with a +2 Trample bonus to-hit. Struck foes that are medium size or smaller and which weigh less than the turtaqua must succeed at a DC 13 Strength saving throw or be knocked prone (giving other attackers +4 against that target until it regains its feet). A Trample attack inflicts 1d4 bludgeoning damage for every two whole hit dice or levels possessed by the Turtaqua.