Cover a large cutting board or baking sheet with a piece of parchment.
Melt the bag of candy melts in a glass measuring cup or small bowl. Use the defrost setting on your microwave to slow the process and avoid overheating the candy melts. Stir every 20 seconds until there are only small pieces left. Then take the container out and stir until those last bits dissolve.
Spread the candy out on parchment with a swirling motion. Don't try and make the bark smooth. The waviness will mimic the surface of a boiling cauldron. Make sure all areas are a minimum of ⅛ inch thick and ½ inch at most.
Arrange the eye balls and frogs on the surface of the candy bark and very gently press into place.
Cut the gummy worms to shorter pieces and tuck the cut end of each into the soft candy. Sprinkle on the round green sprinkles somewhat clustered.
Add the bug shaped candy sprinkles. Then place the Halloween bark in refrigerator to harden.
Use a knife to break this bark up. You may need to cut a couple gummy frogs.