Mimicry. The campestri can mimic any voice or song it has heard, albeit in a nasal falsetto.
Head Butt. Melee Weapon Attack: +0 to hit, reach 5 ft., one target. Hit:1 bludgeoning damage.
Spores (1/Day). A 5-foot radius of spores extends from the campestri. These spores can go around corners, and they have no effect on Constructs, Elementals, Plants, or Undead. Each other creature in the area must make a DC 10 Wisdom saving throw. On a failed save, the creature is incapacitated and its speed is halved, both for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
Campestris are happy-go-lucky mushroom-like creatures with few cares or worries. They are captivated by music, though they can't distinguish a well-played performance from a bad one. If anyone plays an instrument or sings in the campestris' vicinity, the little creatures will happily sing along, each in an obnoxiously nasal falsetto, as they dance and caper around whoever is making the music.