Armor Class 9
Hit Points 52 (7d8 + 21)
Speed 20 ft., swim 20 ft.
Condition Immunities prone
Senses Darkvision 60 ft., passive Perception 10
Languages —
Challenge 2
Aberrant Ground. The ground in a 10-foot Emanation originating from the mouther is Difficult Terrain.
Gibbering. The mouther babbles incoherently while it doesn't have the Incapacitated condition. wis DC 10, any creature that starts its turn within 20 feet of the mouther while it is babbling. The target rolls 1d8 to determine what it does during the current turn:
Bite. m +2, reach 5 ft. Hit: 7 (2d6) Piercing damage. If the target is a Medium or smaller creature, it has the Prone condition. The target dies if it is reduced to 0 Hit Points by this attack. Its body is then absorbed into the mouther, leaving only equipment behind.
Blinding Spittle (Recharge 5–6). dex DC 10, each creature in a 10-foot-radius Sphere centered on a point within 30 feet. 7 (2d6) Radiant damage, and the target has the Blinded condition until the end of the mouther's next turn.
Monster Manual (2024), p. 133