You are stuck in the universe you arrive in for one hour, you will not be teleported somewhere where you instantly die, such as a volcano or space, and when your hour is up you are returned to a random place from the place you left.
The place you arrive at can range from hugely beneficial, such as inside Scrouge Mcducks vault, to rather benign, such as a random street in Kings Landing, or even very dangerous, such as Commoragh in Warhammer 40k. This means you have a 1/3 chance of being in immediate Danger.
After 100 jumps this power wears off. This drawback only activates once every 10 to 12 hours.