How to identify it?
Cap
Cap 4-10 cm across, convex to bell-shaped or broadly convex; grey to brownish gray; surface finely scaly. Flesh thin, easily broken, whitish. Taste pleasant mild.

Scientific Classification

Phylum
Club fungi Class
Mushroom-forming fungi Order
Gilled fungi Family
Pale-spore mushrooms Genus
Tricholoma Species
Grey knight