Spider, Harpoon, Dread (CR 9)

Huge Aberration
Alignment: Usually chaotic evil
Initiative: +3 (Dex); Senses: darkvision 120 ft. and Spot +10
Languages: Common and Undercommon

AC: 19 (-2 size, +3 Dex, +8 natural), touch 11, flat-footed 16
Hit Dice: 9d8+63 (103 hp)
Fort +9, Ref +8, Will +7
Speed: 40 ft., climb 20 ft.
Space: 15 ft./10 ft.
Base Attack +6; Grapple +21
Attack: Bite +11 melee or fang +7 ranged
Full Attack: Bite +11 melee and 2 fangs +2 ranged
Damage: Bite 2d6+7 plus poison, fangs 1d6+3 plus harpooning
Special Attacks/Actions: Harpooning, poison
Abilities: Str 25, Dex 17, Con 23, Int 14, Wis 12, Cha 9
Special Qualities: evasion, spines, web movement
Feats: Ability Focus (poison); Combat Reflexes; Improved Trip; Improved Toughness; Lightning Reflexes
Skills: Balance +11, Climb +22, Hide +7, Jump +26, Spot +10, and Tumble +14
Advancement: 10-15 HD (Huge)
Climate/Terrain: Underground
Organization: Solitary, pair, or nest (3-12)
Treasure/Possessions: Standard

Source: Monster Manual III

Harpooning (Ex): A dread harpoon spider can fire its harpoonlike fangs up to 20 feet (no range increment). A successful hit deals 1d6+1 points of damage as the harpoon hooks the flesh of the target and immediately exudes a thick, sticky glue. The spider can reel in a harpoon as a free action; treat this as a trip attack (+19 bonus) against any creature attached to the fang. Failure indicates that the harpoon rips free (and deals another 1d6+1 points of damage to the victim). This ability is otherwise like the ordinary harpoon spider's harpooning ability.

Poison (Ex): Injury, Fortitude DC 20, initial damage 1d6 Dex, secondary damage 2d6 Dex. The save DC is constitution-based.

Spines (Ex): Any creature striking a dread harpoon spider with its body or a handheld weapon must make a DC 17 reflex save or take 1d8 points of piercing damage from the spider's spines. (Creatures wielding reach weapons, such as longspears, are nor subject to this damage.) The spines also deal an extra 1d8 points of damage on a successful grapple check (much like armor spikes). The save DC is dexterity-based.

As a full-round action, a dread harpoon spider can pick up a large or smaller helpless creature with its legs and impale the body on its spines, dealing 3d6 points of piercing damage. The spider can carry up to 2 large, 8 medium, 32 small, or 128 tiny or smaller creatures in this manner.

A dread harpoon spider patiently waits in ambush for its prey.