Bellowing Tanglewurm
Intimidate checks the color of the creature it sits on, so this Wurm's anthem clause carries a built-in catch: it broadcasts its own color across the team, and on a mono-green board that means every attacker can only be stopped by artifact creatures or other green creatures. That is the structural elegance and the structural flaw in one line. Read against fear, the older keyword that made a creature unblockable except by artifact or black creatures, intimidate is the generalized version, where the relevant blocking exception is whatever color the attacker happens to be rather than a fixed black-and-artifact pair. The lord effect gives it teeth as an evasion engine: a wide green army that shares the same evasion baseline can slip past any board that does not field green or artifact creatures, converting a clogged ground board into one unblocked alpha strike. The 4/4 body is honest filler; the value lives in the anthem, not in combat trades. The weakness is that green is among the most-played creature colors anywhere, so the evasion you are granting is precisely the one most easily neutralized by an opposing green creature. It is an enabler that rewards being built off-axis from the field: pointed against opponents leaning white, blue, red, or black, the green horde finds no legal blockers and the keyword does exactly what it promises.
