n gargantuan animal 

Perception +22; darkvision, web sense

Skills Acrobatics +18, Athletics +23, Stealth +22

Str +8 Dex +5 Con +7 Int -5 Wis +3 Cha -4

Web Sense The spider swarm has imprecise tremorsense to detect the vibrations of creatures touching its web.

AC  30; Fort +25, Ref +21, Will +17

HP 220

Spring Upon Prey [R] (attack) Trigger A creature touches the goliath spider's web while the spider is on it. Requirements Initiative has not yet been rolled. Effect The goliath spider automatically notices the creature and Strides, Climbs, or Descends on a Web before it rolls initiative.

Speed 45 feet, climb 30 feet

Melee [>] fangs +24 (reach 10 feet), Damage 2d12+12 piercing plus goliath spider venom

Ranged [>] web +22 (range increment 60 feet), Effect web tether

Descend on a Web (move) The goliath spider moves straight down up to 120 feet, suspended by a web line. It can hang from the web or drop off. The distance it Descends on a Web doesn't count for falling damage. A creature that successfully Strikes the web (AC 20, Hardness 5, 20 HP) severs it, causing the spider to fall.

Goliath Spider Venom (incapacitation, poison) Saving Throw DC 30 Fortitude; Maximum Duration 6 rounds; Stage 1 2d6 poison and slowed 1 (1 round); Stage 2 2d6 poison and slowed 2 (1 round); Stage 3 paralyzed for 2d4 hours.

Web Tether A creature hit by the spider's web Strike is restrained and tethered to the spider, preventing it from moving farther away from the spider. The spider can have one creature tethered at a time. The DC to Escape or Force Open the web is 30. The tether can be severed with a Strike (AC 20, Hardness 5, HP 20), but this doesn't free the restrained creature.

Bestiary, page 307.