Piercer (CR 1/2)

Tiny Vermin
Alignment: Always neutral
Initiative: -3 (Dex); Senses: darkvision 60 ft., Listen +13, and Spot +3

AC: 16 (+2 size, -3 Dex, +7 natural); 9 underbelly (+2 size, -3 Dex), touch 9, flat-footed 12
Hit Dice: 1d8 (4 hp)
Fort +2, Ref -3, Will +0
Speed: 5 ft., climb 5 ft.
Space: 2 1/2 ft./0 ft.
Base Attack +0; Grapple -13
Attack: Pierce +2 melee
Full Attack: Pierce +2 melee
Damage: Pierce 1d6
Special Attacks/Actions: Improved critical, acid
Abilities: Str 10, Dex 4, Con 11, Int 2, Wis 11, Cha 9
Special Qualities: Vermin
Feats: -
Skills: Hide +4*, Listen +13, and Spot +3
Advancement: 2 HD (Small); 3 HD (Medium-size)
Climate/Terrain: Any underground
Organization: Cluster (5-10) or colony (11-20)
Treasure/Possessions: None

Source: Converted

Improved Critical (Ex): A piercer threatens a critical on an attack roll of 19-20.

Acid (Ex): The piercer's soft underbelly is coated with a corrosive acid that deals 1d6 points of damage if it contacts exposed flesh.

The piercer receives a +8 racial bonus to Listen checks. *The piercer receives a +15 racial bonus to Hide checks when against a background of natural stone.

The piercer attacks by dropping on unsuspecting individuals and impaling them with its shell. Once its attack is expended, the piercer must climb the walls of its lair and resume its position to drop again. On the ground a piercer is easily slain.

The piercer appears as a normal stalactite (1 to 6 ft. long) found on cavern roofs. This is its outer shell. Inside, it appears as a slug with a long tail. A piercer can be identified by the two tiny eyestalks that curl along the side of it.

The Piercer first appeared in the Monster Manual (Gary Gygax, 1977).