Millions of red-eyed locusts blot out the sun. They descend in a ravenous tornado, consuming everything they touch.
All plague swarms have the following features.
Organization solitary or brood (plague swarm plus 1-100 spawn)
Blight (Su) Plague swarms deal additional untyped damage equal to their standard swarm damage. This damage originates from divine power, similar to the spell flame strike. A plague swarm's damage counts as magic and epic for the purposes of bypassing damage reduction.
Multiply (Ex) Plague swarms spawn at an incredible rate. Once per minute, a plague swarm can produce a new swarm of the type listed in its stat block as full-round action. When the plague swarm is not in combat, it typically uses this ability once per minute. If the plague swarm is destroyed, all of the swarms that it spawned also disperse.
Reform (Su) When a plague swarm is dispersed by damage, it is not destroyed. A dispersed plague swarm reforms in 24 hours. Each plague swarm has a unique destruction condition. In addition, because plague swarms are manifestations of divine retribution, placating the deity's rage destroys the swarm instantly.
Sent down by vengeful deities to punish communities that have offended them, plague swarms scour crops, terrorize populations, and lay waste to civilized lands. Normal means of dealing with vermin and pestilence don't drive them off, for these vicious and intelligent mythic swarms carry the destructive blessings of their gods, and breed at an exceptional rate until their spawn consume entire cities. They are single-minded in their devotion to carrying out the furious will of their deities.
Rat Plague Swarm CR 11/MR 8
LE Tiny magical beast (mythic, swarm)
Init +16/-4, dual initiative; Senses darkvision 60 ft., low-light vision, scent; Perception +23
AC 25, touch 17, flat-footed 20 (+4 Dex, +1 dodge, +8 natural, +2 size)
hp 152 (16d10+64); fast healing 5
Fort +11, Ref +16, Will +9; second save
Defensive Abilities reform, swarm traits, unstoppable; DR 10/epic
Speed 30 ft., climb 30 ft., swim 30 ft.
Melee swarm +14 (4d6-2 plus 4d6 blight, curse of lycanthropy, disease, and distraction)
Space 20 ft.; Reach 0 ft.
Special Attacks distraction (DC 19), mythic power (8/day, surge +1d10)
Str 2, Dex 19, Con 8, Int 19, Wis 18, Cha 15
Base Atk +16; CMB —; CMD —
Skills Acrobatics +20, Climb +31, Diplomacy +18, Perception +23, Stealth +31, Swim +31
Languages Abyssal, Celestial, Common, Infernal (can't speak any language); telepathy 200 ft.
SQ hivemind, multiply (rat swarm with curse of lycanthropy [Fort DC 12])
Curse of Lycanthropy (Su) A humanoid of any size who takes damage from a plague rat swarm must succeed at a DC 19 Fortitude save or it contracts lycanthropy and becomes a wererat. Any humanoid who contracts lycanthropy from a rat plague swarm becomes immune to bubonic plague.
Disease (Ex) Bubonic Plague: Swarm—injury; save Fort DC 19; onset immediate; frequency 1/day; effect 1d4 Str damage, 1 Cha damage, and target is fatigued; cure 2 consecutive saves.
Hivemind (Su) A plague rat swarm can maintain constant telepathic communication with every wererat it created with its curse of lycanthropy as long as they are on the same plane. These wererats have an attitude of helpful toward the swarm.
Reform (Su) A rat plague swarm can be destroyed only if a mythic spellcaster (or a non-mythic spellcaster who succeeds at a DC 31 caster level check) affects it with remove disease on the round before the swarm is dispersed. This condition bypasses a swarm's normal immunity to single-target effects.
Locust Plague Swarm CR 15/MR 8
NE Fine magical beast (mythic, swarm)
Init +16/-4, dual initiative; Senses darkvision 60 ft., low-light vision; Perception +24
AC 31, touch 23, flat-footed 26 (+4 Dex, +1 dodge, +8 natural, +8 size)
hp 216 (21d10+101); fast healing 5
Fort +15, Ref +18, Will +13; second save
Defensive Abilities reform, swarm traits, unstoppable; DR 10/epic; Immune mind-affecting effects, weapon damage
Speed 10 ft., climb 10 ft., fly 40 ft. (good)
Melee swarm (5d6 plus 5d6 blight, devour, and distraction)
Space 20 ft.; Reach 0 ft.
Special Attacks devour, distraction (DC 23), mythic power (8/day, surge +1d10)
Str 6, Dex 19, Con 12, Int 5, Wis 18, Cha 9
Base Atk +21; CMB —; CMD —
Feats Ability Focus (distraction), Dodge, Extra Mythic Power, Great Fortitude, Improved Initiative, Improved Lightning Reflexes, Iron Will, Lightning Reflexes, Lightning Stance, Skill Focus (Fly), Skill Focus (Perception), Wind Stance
Skills Climb +12, Fly +35, Perception +24
Languages Abyssal (can't speak)
SQ multiply (locust swarm with the devour ability)
Devour (Ex) A locust plague swarm devours everything in its path. Its swarm attack damages all unattended objects and all attended items that are not magical. Each round, the locusts also damage one attended magic item worn or carried by each creature damaged by the swarm. Each round, the swarm can affect only one magic item per creature, even with its dual initiative. If a creature possesses more than one attended magic item, use the table for items affected by magical attacks to Rulebook determine which magic item the swarm targets. The locusts' powerful jaws count as adamantine for the purpose of bypassing DR and bypass all hardness less than 20.
Reform (Su) A locust plague swarm is truly destroyed only if it devours a good-aligned minor artifact or holy relic.
Bat Plague Swarm CR 17/MR 8
NE Diminutive magical beast (mythic, swarm)
Init +19/-1, dual initiative; Senses blindsense 100 ft., darkvision 60 ft., low-light vision; Perception +34
AC 32, touch 24, flat-footed 24 (+7 Dex, +1 dodge, +8 natural, +2 profane, +4 size)
hp 279 (21d10+164); fast healing 10
Fort +18, Ref +21, Will +13; second save
Defensive Abilities profane protection, swarm traits, unstoppable; DR 10/epic; Immune weapon damage
Speed 5 ft., fly 40 ft. (good)
Melee swarm (5d6 plus 5d6 blight, distraction, and soul bleed)
Space 20 ft.; Reach 0 ft.
Special Attacks create spawn, distraction (DC 26), mythic power (8/day, surge +1d10), soul bleed
Str 6, Dex 25, Con 18, Int 11, Wis 18, Cha 9
Base Atk +21; CMB —; CMD —
Feats Ability Focus (distraction), Ability Focus (soul bleed), Dodge, Extra Mythic Power, Great Fortitude, Improved Initiative, Iron Will, Lightning Reflexes, Lightning Stance, Skill Focus (Fly), Skill Focus (Perception), Wind Stance
Skills Fly +37, Perception +34, Stealth +32
SQ multiply (bat swarm with soul bleed [Fort DC 11])
Create Spawn (Su) A humanoid creature who dies from a bat plague swarm's soul bleed ability rises from death as a vampire in 1d4 days. This vampire is under the command of the swarm, and remains enslaved until the swarm is destroyed. The swarm can have enslaved spawn whose Hit Dice total no more than twice its own; any spawn it creates that would exceed this limit become free-willed undead.
Profane Protection (Su) A bat plague swarm gains a +2 profane bonus to its Armor Class from its divine creator.
Reform (Su) A bat plague swarm is truly destroyed only if it is dispersed in the area of a hallow spell.
Soul Bleed (Su) A creature that takes damage from a bat plague swarm begins to bleed from its body and its soul. Each round, a creature under the effects of soul bleed takes 1d4 points of Constitution bleed damage and gains 1 negative level. A creature affected by soul bleed can't be healed by magical healing from a non-mythic source. A mythic caster can attempt a DC 24 caster level check to heal a creature under the effects of soul bleed. If the caster succeeds, the soul bleed ends. Otherwise, any creature can end a soul bleed effect with a successful DC 35 Heal check. Twenty-four hours after a creature takes negative levels from soul bleed, it must attempt a separate DC 26 Fortitude save for each negative level. If it succeeds at a save, that negative level is removed. If it fails, that negative level becomes permanent. The save DC is Constitution-based.