"The rings on Hoopa's body can warp space and allow it transport items by passing them through its hoop. Hoopa Unbound is said to be Hoopa's true form and is said to have the power to bend dimensions. This allows it to seize anything in the world. As seen in the anime, either form can travel through its rings and Hoopa Unbound has the ability to control and summon powerful Legendary Pokémon."
This feature would make Hoopa a lot more useful