An unsual and parasitic mushroom that appears as two forms: a normal, steel grey looking mushroom, and a whiteish globular mass when it is parasitizing. Is a steel gray, pink-spored, gilled mushroom with a cap that is at first convex with an inrolled margin, and later more or less flat. The gills are usually at least partially decurrent, they run down the stem. When parasitizing Armillaria mellea, it appears as a glob of pale fungal flesh that looks like a malformed puffball. When sliced open, the glob has pinkish areas or veins inside.
Can be found growing scattered or gregariously near decaying wood, or in leaf litter near decaying wood; usually encountered with Armillaria species fruiting in the vicinity; late summer and fall.