It is believed that the centre of our universe(or multiverse if you call it)is the place which holds all the stars and planets and other celestial bodies in place. So it will be place having the highest concentration of energy. The stars in this region will be the largest ones.When these stars die ie. convert all their hydrogen into helium they themselves get pulled into their own centre. they more they get pulled in the more powerful the pull gets. Finally it gets so powerful that even light cannot escape. Imagine that the black hole became so big and powerful that it has pulled a star in and is about to swallow it (By swallowing I mean compressing the whole thing to one point). If you get the unusually rare chance to see this unusually process from a safe distance, you would see that the star would accelerate as it is about to be compressed but just before the spectacle the star seems to slow down and then suddenly it disappears. This is because when the sun comes close to the Black Hole the gravitational pull of the black hole will slow down the light beams. This just proves the power of a black hole.I hope I answered your question.