Massive roots are enormous, ancient tree roots encountered deep within Fangorn Forest. They are among the hazards that make navigation through Fangorn difficult, forming natural barriers between rooms and contributing to the zone's sense of impenetrable, primordial forest.
In MUME, massive roots appear as environmental objects that may block movement or define room boundaries within the Fangorn zone. They are a reminder that Fangorn is not merely a forest but a living, dangerous presence — the domain of the Ents.