Colossal Maggot

Keen Smell. The Colossal Maggot has advantage on Wisdom checks that rely on smell.

Feast. If the Colossal Maggot start its turn stuck to a creature it can start to eat its way into it, the creature takes 3d8+6 piercing damage, each round the Colossal Maggot holds up to the creature the Colossal Magoot deals an extra 3d8+6 piercing damage. 

Acidic Stomach. A creature that starts its turn within the stomach of the Colossal Maggot takes 2d6 acid damage at the start of the Colossal Maggot´s turn.

Parasitic Bite. Melee Weapon Attack: +8  to hit, 5ft range, one target, 3d8+6 piercing damage, the Colossal Maggot leches to the creature it bites sticking to it, a creature can attempt to take it of by succeeding a DC 18 Strength Saving Throw.

Swallow. If the Colossal Maggot hits a creature with its Parasitic Bite on its turn it can atempt to swallow the creature provided it is large or smaller, the creature must succeed in a DC 18 Strenght saving throw being swallowed on a failure.

A swallowed creature has full cover, its movement is reduced to 0, and it cannot hear nor see past the dark interior of the maggot. A creature may as an action force its way out of the maggot, by succeeding in a DC 18 Strenght saving throw, or by dealing 10 or more damage to the Colossal Maggot on its turn after wich the Colossal Maggot vomits the creature within an unocupied 5ft of it. 

Anti Magical Mucus. When the Maggot is targeted or within the area of a spell or other magical effect it can use its reaction to roll a d10. On a 10 the triggering effect has no effect on the Maggot