Wurmcoil Engine

Death Touch (Toxin). Once per turn, when the wurmcoil makes an attack against a creature and hits it can use its Death Touch effect. When used, the wurmcoil forces the creature that it hit to make a DC 20 constitution saving throw. On a fail, the creature has death inflicted upon it and at the start of all their turns they take 1 damage but at the end of the turn it doubles the damage for the next turn (tdlr; 1,2,4,8,16,32). This effect can be ended by a greater restoration or any other similar effect.

Life Link (Harvest). Once per turn, when the wurmcoil makes an attack against a creature and hits it can use its Life Link effect. When used, the wurmcoil forces the creature that it hit to make a DC 20 constitution saving throw. On a fail, the wurmcoil adds that monsters DNA and Genetics to its list as well as it regains hit points equal to the damage dealt (Mainly meant for Silas so he can maybe add those effects to his sessions, I think it is cool but IDK about him). On a success, the wurm coil regains half the damage dealt with the attack.

Multiattack. The wurmcoil makes two attacks with its bite attack and one with its piercing shot/pull.

Bite. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 29 (4d10 + 8) [piercing] damage. 

Piercing Shot. Ranged Weapon Attack: +14 to hit, range 500 ft., one target. Hit: 24 (3d10 + 8) [damage type] damage, and the target is grappled (escape DC 20). While grappled in this way, a creature's speed isn't reduced, but it can move only in directions that bring it closer to the wurmcoil. A creature takes 5 (2d10) slashing damage if it escapes from the grapple or if it tries and fails. The wurmcoil has two piercing shots built within its maw that it can use to grapple up to two creatures at a time.

Reel In: The wurmcoil pulls the creatures grappled by its Piercing shot up to 50 feet closer.