void Form. The elemental can move through a space as narrow as 1 inch wide without squeezing. A creature that touches the elemental or hits it with a melee attack while within 5 feet of it takes 4 (1d8)  necrotic damage. In addition, the elemental can enter a hostile creature's space and stop there. The first time it enters a creature's space on a turn, that creature takes 2 (1d4)  damage to a random ability score.if a ability score is reduced to 0 by this effect the target is reduced to 0 hp. the ability damage is restored on a long rest unless they had exhaustion during that long rest.

hungering void 

whenever the elemental reduces an object or creature to 0 hp the creature dies instantly and the elemental heals 2d6 health or makes one additonal touch attack 

Multiattack. The elemental makes two touch attacks.

Touch. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 9 (2d6 + 2) necrotic damage. If the target is a creature  it takes 2(1d4) damage to a random ability score.if a ability score is reduced to 0 by this effect the target is reduced to 0 hp. the ability damage is restored on a long rest unless they had exhaustion during that long rest.