Maggot, Giant (CR 1/2)

Small Vermin
Alignment: Always neutral
Initiative: +1 (Dex); Senses: darkvision 60 ft.

AC: 13 (+1 size, +1 Dex, +1 natural), touch 12, flat-footed 12
Hit Dice: 2d8+2 (11 hp)
Fort +1, Ref +4, Will +0
Speed: 20 ft.
Space: 5 ft./5 ft.
Base Attack +1; Grapple -5
Attack: Bite +3 melee
Full Attack: Bite +3 melee
Damage: Bite 1d6-2
Special Attacks/Actions: -
Abilities: Str 7, Dex 13, Con 13, Int -, Wis 10, Cha 2
Special Qualities: vermin traits
Feats: Weapon Finesse
Skills: -
Advancement: 3-4 HD (Small); 5-8 HD (Large)
Climate/Terrain: Any
Organization: Solitary, pair, mess (3-5), or infestation (6-11)
Treasure/Possessions: None

Source: Underdark

Giant maggots usually attack living creatures only in self-defense, but if food in the local area becomes scarce, they can become predators.

Giant maggots are the larval forms of various giant insects. Because they feed on decaying living matter, they are usually found around the corpses of large creatures such as hydras, dragons, giants, and dinosaurs, as well as in large piles of excrement or decaying plant matter. Some types of maggots are aquatic or amphibious.

A giant maggot resembles a white or gray worm. Occasionally one has tiny legs that make it look like a pale caterpillar.

The life span of the giant maggot is short. Its fat, wormlike body is about 1 foot long when it hatches from its shiny white egg. Over the course of two weeks, it grows to about 3 feet in length, then changes to its adult insect form.