Hailstorm is one of many power-enhancing Mini-Cons scattered across Earth. A member of the Blue Mini-Con Team, when Powerlinxed to a larger Transformer, Hailstorm transforms into a rocket launcher that fires four rockets at once.
Transformers Playstation 2 Game
Hailstorms's Mini-Con storage panel was discovered in the Amazon atop a high peak, guarded by a Heavy Unit Decepticlone. It was only with the use of Slipstream's glider-pack that the Autobots were able to retrieve him.
Following the defeat of Megatron, he and the other Mini-Cons returned to Cybertron and helped form the Matrix Cannon, Nemesis Shield and Vanguard Booster, giving the Autobots the power needed to destroy Unicron.