Waste not, want not.
The foam tray from your chicken nuggets or meat of choice might make a good trash bag stuffer for you. But it’s a cheap and effective hill for miniature wargaming for me. It’s just the right size for a decent hill, already sloped for reasonable movement of models on and off of the terrain piece, and it’s inexpensive. Plus, it’s a “green” way to recycle your trash. It’s actually called “upcycling.”
Make sure to use soap and hot water to clean the tray. Common sense applies here.
Spray the tray with some textured paint, or add texture using a mixture of white glue and sand.
Spray the entire piece with either black or dark brown spray paint. When dry, paint it with a dark brown color, and then highlight it with a lighter brown color. If you wish, add some green highlights to simulate grass.
Apply white glue, and flock. Adding some static grass, and maybe some field grass will finish it off.
Then, it’s ready to go. You have a functional hill for playing a few games of WARMACHINE and HORDES.
Keep rolling sixes!