Make a small amount of powder that when is mixed with water it will make a "bloody" mess.
Step 1: Materials
Red food coloring, tin foil, and an oven. Simple.
Step 2: Make
Preheat oven to 325. Indent tin foil and add coloring in middle. Bake for 6 - 8 min. Remove with knife carefully. MAKE SURE HANDS ARE DRY WHEN HANDLING.