Red Magic Dust
Red Magic Dust is a Crafting Ingredient in Cubic Castles. Forging them to Red Magic Gem (an ingredient in order to craft Harm Wand) is the only way to use them.
Red Magic Dust can be obtained by catching Faries, which is in Forest Mines and Tropical Mines. However you can find them in bought Rooms/Realms with forest or tropical theme.
Blue Magic Dust