Amalgamate

Absorb. The amalgamate can absorb the bodies of deceased creatures who it shares a space with, when it does so it regains hit points equal to the creatures CR or the Players level. This happens when the Amalgamate starts its turn in the same space as a deceased organic creature.

Multi-Conscious Organism. As a result of having several consciousnesses present within it's mental frame the amalgamate has advantage on any Wisdom Saving throws it makes.

Voices of the dead. The Amalgamate can mimic the speech and tone of any creature it assimilates using its absorb feature, creatures can attempt to perceive through the imitation by making a wisdom (Insight) check contested by the Amalgamates charisma (deception) check.

Multi-Attack. When the amalgamate takes the attack action it can make either a bite, a maul and a pseudopod attack or 2 pseudopod attacks.

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., 1 target. Hit: 11 (2d6 + 3) [piercing] damage. 

Maul. Melee Weapon Attack: +6 to hit, reach 5 ft., 1 target. Hit: 13 (2d8 + 3) [slashing] damage. 

Pseudopod.  Ranged Weapon Attack: +5 to hit, range 20/30 ft., 1 target. Hit: 8 (1d10 + 2) [psychic] damage.

Due to the sheer stream of consciousness within the amalgamate the creature can react quickly and perform multiple tasks in coherence with ease affording it additional actions each round, every round the amalgamate can take 3 legendary actions which recharge at the beginning of each of its turns.

Struggle (Costs 1 Action). The amalgamate immediately grants itself 2d10 temporary hit points that last until the start of the amalgamates next turn, the amalgamate can only use this legendary action once per round.

Amorphous (Costs 1 Action). The amalgamate immediately moves 20ft without taking opportunity attacks.

Constrain (Costs 2 Actions). The amalgamate immediately makes a grapple check against a target within 5ft, if this check succeeds the target is considered restrained, blinded and deafened this grapple lasts until the creature uses their action and successfully beats a DC 14 strength (Athletics). While this grapple is active the amalgamate can not target another creature with this grapple, the target takes 1d6 psychic damage at the start of each turn and the amalgamates movement speed is reduced to 10ft.