In the game Kirby Air Ride, the game about half of the series is based on, the hydra can be obtained in the city trial mode by finding all 3 hydra pieces. Unlike the Dragoon, it has some flaws. The Hydra is really fast, and can destroy most of the stars in one hit, making it a tyrant in the battlefield. However, it has some flaws. When you first get it, it will not move. Thats right, like the Bulk Star, you have to CHARGE it, and it takes FOREVER to charge. However, the Bulk Star runs out of fuel at about the same pace as it charges up for fuel. The Hydra follows this, so it does not run out of fuel for a long time. (Longer than the charge time)
The Hydra is one of White Kirby's Kirby Attacks. It does not need attack pieces, instead it needs the three Hydra Pieces, which are stolen by Blue Kirby early in the game.
Every stat of the Hydra is modified, (higher/lower than average) besides its Turning.
He's cousins with the Bulk Star.