Amalgamate - Sin Eater

Consume All. The Amalgamate lives to consume organic life forms in order to grow in size, and power. The Sin Eater will attempt to eat a humanoid within it's range, if it succeeds, it will grow 1d4 feet in size, and it's hit points will increase by 3d8

Spellcasting. The Amalgamate - Sin Eater is a 2st-level spellcaster. Its spellcasting ability is [ability score] (spell save DC 12, +2 to hit with spell attacks). The Amalgamate - Sin Eater has following spells prepared:
Cantrips (at will): Acid Splash

Core Form. The Amalgamate, if dropped to exactly 0 hit points, loses all of it's flesh mass, and is reduced to the 2 ft tall/wide Core. A large orb appearing as if made of a dark tinted glass, with a burning red interior. The core has 5HP, and a moving speed of 30ft. The Amalgamate's Core's main directive is to avoid being destroyed, and will actively run from threat's that it perceives. 

Vestigial Arms. Melee Weapon Attack: +1 to hit, reach 5 ft., 1 target. Hit: (1d8+ 1) bludgeoning damage. 

Tendril. Ranged Attack: +3 to hit, range 10 ft., 2 targets. Hit: (2d6 + 1) Bludgeoning damage + Acid Damage

Ensnare. Ranged Attack: +2 to hit, range 10 ft., 1 target. On a successful hit, the target is grappled.

Acid Splash. Ranged Spell Attack: +2 to hit, range 60ft.  Hit: (1d6) Acid Damage

Ungodly Shriek. The Amalgamate unleashes the screams of those used to form it's body, all within a 20 ft. radius of the Amalgamate must make a Wisdom saving throw (DC13.) On failure, the creature takes 1d8 psychic damage, and is stunned for a round. On success, the creature takes 1d4 psychic damage, and resists the stun.

Consume.  (Duration: 3 Rounds.) The Sin Eater will attempt to assimilate a grappled creature. The creature must succeed on a strength check (DC 15) or begin to be consumed. Other creatures can decrease the DC by taking an attack of opportunity on the Sin Eater, as this action leaves it open to attack, or by using an action to aid the grappled creature's escape. The creature being consumed takes 1d8 Acid Damage while being consumed. If the creature is not broken free within 3 rounds, the creature is swallowed whole into the Sin Eater's mass, where it will take 2d8 Acid Damage per round until the creature is killed, or the Sin Eater takes damage equal to the creature's Hit Points. When a creature is killed by this action, the Sin Eater's Consume All trait comes into effect.

Retreat. The Sin Eater will attempt to flea in order to consume a nearby Lifeform.

Vengeful Grasp. Upon being stuck with a melee attack within 7 feet of the Sin Eater, it will roll a d20 against the attacking creature's DEX saving throw, if the Amalgamate beats the attacker's roll, the attacker is now grappled by the creature.

Rampage of Entanglement. The Sin Eater selects 3 targets, and attempts to use the Ensare action on all three targets.