If the playing surface is Glass, you can flood the top with Acetone it will seep in around the edges and soften goop. Then take a single edge razor blade and using the corner go around the edges an few times and then put some more acetone on it as it will evaporate pretty fast. Once you can get the blade in there all the way around you may need to add some more acetone and the goop will begin to get really soft then you can pry the glass up without breaking it. If all else fails ....like everyone else said....Put a piece of cloth over the glass and smack it with a hammer!