Legendary Resistance 2/d If the shroom fails a saving throw, it can choose to succeed instead.   Poisonous Spores If the shroom is hit with an attack it immediately releases poisonous spores in 10ft. radious. On a failed DC 18 Constitution saving throw anty creature in range suffers 33(6d10) 6d10 poison damage and is poisoned 1 minute.On a success, it takes no damage and isn't poisoned. (If you feel this is too strong, make it a reaction dealing 10d8 10d8 dmg to a single person)   Camouflage When still, the shroom is indistinguishable from other stationary shrooms unless a person succeeds on DC 20 Wisdom(Nature) check.   Muddy Earth As a bonus action the shroom can use its underground hyphaye to turn nearby earth into sticky mud, making it difficult terrain in 120ft. radious. Any creature in the mud must make a DC 14 Dexterity saving throw at the beginning of each of its round or be grappled (escape DC 14). The shroom is immune to this effect.