Stronghold is one of many power-enhancing Mini-Cons scattered across the Earth. A member of the Blue Mini-Con Team, when Powerlinxed to a larger Transformer, Stronghold provides an incredible boost to that Transformer's armor strength, the highest armor boost of all the Mini-Cons.
Transformers Playstation 2 Game
Stronghold's Mini-Con storage panel was discovered on Megatron's Pacific island base, not far from an abadoned human settlement. 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.