It’s an item which changes form (from one item to another) over time. We like to call the changes “morphs,” and the different items “states” or “stages.” The number of stages (anywhere from a few to several), appearance of future stages, and time in between morphs (could be days or weeks) will always be a surprise -- it’s more fun that way! When your Experiment makes its last morph, all of the previous item states or stages will appear in your Inventory. From there, you can do whatever you like with the items: they'll behave just like any other "normal" item.