correct, implosion.
correct, black hole.
And yes, it is possible, I think so. Because when an explosion occurs, the bricks are set to go off at a certain angle. If we put a negative sign, or reversed that angle, then it would go inwards. As for the players sucking in, i think its possible. If players can be blown outwards from an explosion, i think they should be able to be pulled inwards. Not sure though