I'm thinking maybe I'll modify the Carnivorous Worm Swarm by adding a Deadly Worm Swarm and tweak the squirming doom note to become "Spell functions like creeping doom, but calls deadly worm swarms instead of centipede swarms."
I propose the following for said swarm:
Swarm, Deadly Worm
Fine Vermin (Swarm)
Hit Dice: 9d8 (40 hp)
Initiative: +0
Speed: 10 ft. (2 squares), burrow 10 ft., swim 10 ft.
Armor Class: 18 (+8 size), touch 18, flat-footed 18
Base Attack/Grapple: +6/—
Attack: Swarm (2d6 plus poison and slipping hazard)
Full Attack: Swarm (2d6 plus poison and slipping hazard)
Space/Reach: 10 ft./0 ft.
Special Attacks: Distraction, poison, slipping hazard
Special Qualities: Amphibious, blind, immune to weapon damage, swarm traits, tremorsense 30 ft., vermin traits
Saves: Fort +6, Ref +3, Will +3
Abilities: Str 1, Dex 11, Con 10, Int —, Wis 10, Cha 2
Skills: Swim +8
Feats: —
Environment: Any swamp or aquatic and warm forests
Organization: Solitary, squirm (2-4 swarms), or doom (7-12 swarms)
Challenge Rating: 4
Treasure: None
Alignment: Always neutral
Advancement: None
Level Adjustment: —
A roiling mass of vividly colored worms, the largest of the slimy creatures is the size of a normal earthworm.
These miniscule carnivorous worms are venomous and voracious. Most live in water but a few species inhabit the moist soil of forests and jungles. Deadly worms have a painful bite roughly equivalent to a hornet's sting. Normally solitary, a single worm poses no threat to humanoid sized creatures but may bite if handled. However, a swarm of deadly worms poses a lethal danger to any fleshy creature it encounters. Fortunately, swarms only gather in extraordinarily abnormal circumstances (such as the
squirming doom spell).
Combat
A deadly worm swarm seeks to surround and attack the largest and freshest source of meat it encounters, which is usually living prey. The swarm deals 2d6 points of damage to any creature whose space it occupies at the end of its move.
Amphibious (Ex): Deadly worms can breathe air as well as water.
Blind (Ex): Deadly worms are immune to gaze attacks, visual effects, illusions, and other attack forms that rely on sight.
Distraction (Ex): Any living creature that begins its turn with a swarm in its space must succeed on a DC 14 Fortitude save or be nauseated for 1 round. The save DC is Constitution-based.
Poison (Ex): Injury, Fortitude DC 14, initial and secondary damage 1d4 Dex. The save DC is Constitution-based.
Slipping Hazard (Ex): Any creature that enters the space of a deadly worm swarm must make a successful DC 14 Reflex save or fall. This save is repeated at the end of the swarm's move each round that the creature remains within the area. A creature can walk within or through the space of worms at half normal speed with a DC 14 Balance check. Failure means it can't move that round (and must then make a Reflex save or fall), while failure by 5 or more means it falls (see the Balance skill for details). The save DCs are Constitution-based.
Skills: A deadly worm has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. A deadly worm uses its Dexterity modifier instead of its Strength modifier for Swim checks. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.