Augubil, The Great Mother, The Sleeper of the Swamp, The Wandering Stalker, The Feasting Famine

Amphibious. Augubil can breath air and water. 

Innate Spellcasting. Augubil‘s innate spellcasting ability is Charisma (spell save DC 19, +11 to hit with spell attacks). Augubil can innately cast the following spells, requiring no material components:
At will: thorn whip, poision spray
2/day each: contagion, entangle, fog cloud, moonbeam, transport via plants,                               3/day each: cloudkill, wall of thorns.

Legendary Resistance (3/Day). If Augubil fails a saving throw, it can choose to succeed instead.

You Magic Resistance. Augubil has advantage on saving throws against spells and other magical effects.

Magic Shielding.  When a spell attack roll is made against Augubil, she is considered in 1/2 cover at all times, 3/4 cover in 1/2 cover, and full cover in 3/4 cover. On a 1 the spell is reflected at the caster.  

Stench. Any creature that start its turn within 10 feet of Augubil must succeed on a DC 15 Constitution saving throw or be poisoned until the start of the creature next turn. On a succesful saving throw, the creature is immune to the stench of Maximus for 24 hours.

Speak with Frogs and Toads. Augubil can communicate simple concepts to frogs and toads when it speaks in Bullywug.

Swamp Camouflage. Augubil has advantage on Dexterity (Stealth) checks to hide in swampy terrain.

Multiattack. Augubil can use its Frightful Presence or Hypnotic Gaze. She then makes four attacks: two with her claws, one with her leaping strike, and one with her tongue. She can use her Swallow instead of her tongue.

Claw. Melee Weapon Attack: +18 to hit, reach 10ft., one target. Hit: 32 (5d8 + 9) slashing damage.

Leaping Strike. Augubil leaps 20 feet toward a creature. That target must succeed on a DC 20 Dexterity saving throw or take 32 (5d12) bludgeoning damage and be be knocked prone. If the target is prone, Augubil can make one claw attack against it as a free action.

Tounge. Melee Weapon Attack: +18 to hit, reach 20 ft., one target. Hit: 34 (4d12 + 9) bludgeoning damage and 13(4d6) acid damage.

Frightful Presence. Each creature of Augubil's choice within 120 feet of her and aware of her must succeed on a DC 17 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, with disadvantage if Augubil is within line of sight, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to Augubil's Frightful Presence for the next 24 hours.

Hypnotic Gaze. Choose one creature that you can see within 25 feet of Augubil. If the target can see or hear her, it must succeed on a DC 19 Wisdom saving throw or be charmed by Augubil until the end of her next turn. The charmed creature's speed drops to 0, and the creature is incapacitated and visibly dazed. The creature may repeated the saving throw if it takes damage  

Swallow. Augubil makes one tounge attack against a Large or smaller creature within range. If the attack hits, the target takes the tounge's damage, and the target must make a DC 20 escape check. If failed the target is swallowed. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside Augubil, and it takes 53 (15d6) acid damage at the start of each of Augubil’s turns.

If Augubil takes 60 damage or more on a single turn from a creature inside her, Augubil must succeed on a DC 20 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone in a space within 10 feet of Augubil. If Augubil dies, a swallowed creature is no longer restrained by her and can escape from the corpse by using 30 feet of movement, exiting prone.

Augubil can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Augubil regains spent legendary actions at the start of its turn.

Spell. Augubil casts a spell.

Attack. Augubil makes one claw attack or tail attack.

Belly Flop (Costs 2 Actions). Augubil makes one leaping strike attack.

Egg Hatch (Costs 3 Actions). Augubil tosses 1d6 eggs off her back at tosses them 20 ft. Any creature occupying the targeted area must make a DC 15 Dexterity saving throw or take 7 (2d6) bludgeoning damage. The eggs with hatch on Augubil’s next turn. They emerge as sunken ones, acting on Augubil’s initiative.