Answer:
I'm sometimes white and always wrong. I can break a heart and hurt the strong. I can build love or tear it down. I can make a smile or bring a frown.
Some try to hide, some try to cheat. But time will show, we always will meet. Try as you might, to guess my name. I promise you'll know, when you I do claim.
What can be underwater, under fire, on fire and taking water all at the same time?
White fat and fluffy, May even look like a puppy. Seems heavy but is light, Floats about without a worry, But if it turns dark you have to hurry!
People are hired to get rid of me. I'm often hiding under your bed. In time I'll always return you see. Bite me and you're surely dead.
You use it between your head and your toes, the more it works the thinner it grows.