Shifting Slime

A type of large and fluid ooze, shifting slimes have an iridescent hue to them which seems to shift as they move. According to slime-wranglers, they can use magical energy to create an eerie bioluminescence. Shifting slime residue is a highly sought after potent reagent, but it is hard to come by. Despite their size, these slimes are elusive and generally spend their time below ground where visibility is low. They can be quite difficult to locate when they conceal themselves in the subterranean darkness, though these strange creatures are known to leave trails of bioluminescent residue to lure in prey.
After absorbing magical energy, these slimes will change color based on the type of power absorbed. Because of the rarity of shifting slimes, only a handful of people have witnessed these changes. But, over generations, skilled slime-wranglers have managed to record which color a shifting slime will turn in response to different types of magic.