If we created it on earth? It would swallow the earth and destroy us. But to create one we would have to gather a mass greater than the moon onto the earth, so

If we created it on earth? It would swallow the earth and destroy us. But to create one we would have to gather a mass greater than the moon onto the earth, so the gravitational effects would probably destroy us before the black hole formed. Black holes aren't as scary as people think. If being next to a black hole of mass M is bad, then being next to a rock of mass M is probably just as bad.