How can you improve drainage/raise elevation in a muddy horse paddock? Also, what is muck buster?

You can't do much at the moment if everything is flooded. And I can't give you exact numbers for fixing it. When the water starts going down I would sc out the mud you can and put down pea gravel. We use that in a lot of paddocks at our barn. If you use the gravel though you have to make sure there is a soft area for your horse to lie down. If you can use the mud to make a bit of a slope and let it sit for a little, then put the gravel in. The water will drain through the gravel rather than soaking the paddock. Three inches of gravel max for depth, too deep and it's hard to walk through.