Here's a starting stat block:
Gaze Spider
Large Magical Beast (Extraplanar)
Hit Dice: 5d10+20 (47 hp)
Initiative: +2
Speed: 40 ft. (8 squares), climb 20 ft.
AC: 16 (–1 size, +2 Dex, +5 natural), touch 14, flat-footed 14
Base Attack/Grapple: +5/+12
Attack: Bite +7 melee (1d8+4)
Full Attack: Bite +7 melee (1d8+4)
Space/Reach: 10 ft./5 ft.
Special Attacks: Paralyzing gaze
Special Qualities: Darkvision 60 ft., low-light vision
Saves: Fort +8, Ref +6, Will +4
Abilities: Str 17, Dex 14, Con 19, Int 5, Wis 13, Cha 10
Skills: Climb +11, Hide -2, Listen +5, Move Silently +6
Feats: Ability Focus (gaze), Iron Will
Environment: Infinite Layers of the Abyss
Organization: Solitary, pair, or pack (5-8)
Challenge Rating: 6
Treasure: None
Alignment: Always chaotic evil
Advancement: 6–8 HD (Large); 9–15 HD (Huge)
Level Adjustment: -
This eight-foot long arachnid has short legs and a bulbous abdomen. Its eight eyes are much larger than normal for a spider of its size.
A common denizen of Kalistes' dimension are the fierce gaze spiders.
A typical gaze spider’s body is 8 feet long. It weighs about 900 pounds.
Gaze spiders cannot speak.
COMBAT
Gaze spiders attempt to paralyze foes with their gaze, then close to finish the others with their bite.
Paralyzing Gaze (Su): Paralysis 1d6 rounds, 30 feet, Fortitude DC 14 negates. The save DC is Charisma-based.
Skills: A gaze spider has a +8 racial bonus on Climb checks and can always choose to take 10 on a Climb check, even if rushed or threatened.
The gaze spider first appeared in the SSI computer game Pools of Darkness, (1991).