I arrive to ruin the fun, Before the show has even begun, I beg for eyes, for ears to hear, Yet all just wish I'd disappear

Forwards I am heavy. Backwards I am not. What am I?

I am the ghost of morsel's past, invisible to the naked eye. Every time you let me pass, you swear that something died.

I'm one and many by name, And yet I am just a game. As your property empire expands, Familial tensions might lead to thrown hands.

You trash my provisions and won't let me sleep, So I block all your entrances, scrub, patch, and sweep, Throw out what you've built and lock up all the food, And bring in Miss Fluffy to stop you for good!