Swarm

A swarm is a collection of Fine or Diminutive creatures (usually creatures of the vermin or animal types, but not always) that acts as a single creature. Swarms include flocks of birds, swarms of bees, writhing nests of poisonous snakes, and any other conglomeration of creatures that tends to move as a solid mass.
A swarm has the characteristics of its original type, except as noted here.
A swarm has a single pool of Hit Dice and hit points, a single initiative modifier, a single speed, and a single Defense. The swarm makes saving throws as a single creature. A single swarm occupies a square (if it is made up of nonflying creatures) or a cube (if comprised of flying creatures) 5 feet on a side, but its reach is 0 feet. To attack, the swarm moves into an opponent's fighting space, which provokes an attack of opportunity. It can occupy the same fighting space as a creature of any size, since it crawls all over its prey. A swarm can move through squares occupied by enemies and vice versa without impediment, although the swarm may provoke an attack of opportunity if it does so. A swarm can move through cracks or holes large enough for its component creatures. Larger swarms are represented by multiple swarms, or multiple 5-foot squares.
Swarms are presented in a variety of sizes, with a typical example of their type.
Species Traits
Swarms have the following traits:
Swarm : Swarms are not subject to critical hits or flanking. A swarm takes half damage from ballistic, slashing, and piercing weapons. It is immune to any spell or effect that targets a specific number of creatures (including single-target spells such as disintegrate) unless the swarm is susceptible to mind-affecting effects. (If it has a mind, it has a single hive mind that can be targeted by a mind-affecting spell, though swarms of vermin are mindless and thus immune to such effects.) A swarm takes a -10 penalty on saving throws against spells or effects that affect an area, such as many evocation spells or grenade-like weapons. If the area effect attack does not allow a saving throw, the swarm takes double damage instead.
A swarm that fails a Fortitude save against massive damage disperses and does not reform until its hit points return to full.
Swarms don't make standard melee attacks. Instead, they deal automatic damage to any creature whose space they occupy at the end of their move, with no attack roll needed. Some swarms also have acid, poison, blood drain, or other special attacks in addition to normal damage. A swarm's attacks are nonmagical unless the swarm's description states otherwise. Damage reduction sufficient to reduce a swarm attack's damage to 0, incorporeality, or other special abilities may make a creature immune (or at least resistant) to damage from the swarm. Swarms cannot attempt trip or grapple checks, nor can they be tripped or grappled themselves.
Swarms do not threaten creatures in their square and do not make attacks of opportunity with their swarm attack. However, they distract foes whose squares they occupy, as described below.
Distraction (Ex): Any intelligent creature vulnerable to a swarm's damage that begins its turn with a swarm in its fighting space is distracted. The target must attempt a Fortitude save (DC 10 + swarm's Hit Dice) or become nauseated for 1 round by the intense pain of countless bites, stings, and pinches. A creature that takes no damage from the swarm's attack is not subject to distraction. Nauseated creatures are unable to attack or do anything else requiring attention or concentration; the only action a nauseated creature can take is a single move action per turn. Even if the target creature succeeds at a Fortitude save, it is still vulnerable to the swarm's distraction. It is difficult to undertake complex actions while covered by a swarm. Casting or concentrating on a spell requires a Concentration check (DC 20 + spell level). Using skills requiring patience and concentration (such as moving silently or opening a lock) requires a Concentration check (DC 20). If the check fails, the target creature is unable to complete the action.
Sentience (Ex): Most swarms have the Intelligence of a single member of the swarm. Sentient swarms have a hive mind. A swarm with a hive mind has a higher Intelligence score but is susceptible to mind-affecting spells as if it was a single intelligent creature. Sentient swarms have skills as a magical beast (2 x.Int score, plus 1 additional skill point per HD beyond 1 HD).
Monstrous Spider Swarm
Vermin: A monstrous spider swarm is immune to mindaffecting attacks.
Poison (Ex): Bite-Fortitude save (DC 14); initial and secondary damage 1d4 Str.
Resistance to Massive Damage (Ex): A monstrous spider swarm gains a +5 species bonus on Fortitude saves to negate the effects of massive damage.
Darkvision (Ex): A monstrous spider swarm can see in the dark up to 60 feet. Darkvision is black and white only, but it is otherwise like normal sight, and the spiders can function with no light at all.
Monstrous Spider Swarm: CR 2; Medium vermin (swarm of Tiny vermin); HD 4d8; hp 18; Mas 10; Init +3; Spd 20 ft., climb 10 ft.; Defense 13, touch 13, flat-footed 10 (+3 Dex); BAB +3; Grap -; Atk swarm (1d6 plus poison, swarm); Full Atk swarm (1d6 plus poison, swarm); FS 5 ft. by 5 ft.; Reach 0 ft.; SQ swarm, vermin, distraction, poison, resistance to massive damage, darkvision 60 ft.; AL none; SV Fort +4, Ref +4, Will +1; AP 0; Rep +0; Str 1, Dex 16, Con 10, Int -, Wis 10, Cha 2.
Skills: Climb +3, Move Silently +8, Spot +5.
Feats: None.
Advancement: None.
Piranha Swarm
Aquatic: A swarm of piranha can move in water without making Swim checks and cannot drown in water.
Low-Light Vision (Ex): A swarm of piranha can see twice as far as a human in starlight, moonlight, torchlight, and similar conditions of poor illumination. It retains the ability to distinguish color and detail under these conditions.
Piranha Swarm: CR 3; Medium animal (swarm of Diminutive animals); HD 6d8+6; hp 33; Mas 12; Init +3; Spd swim 30 ft.; Defense 14, touch 13, flat-footed 11 (+3 Dex, +1 natural); BAB +4; Grap -; Atk swarm (2d6, swarm), Full Atk swarm (2d6, swarm); FS 5 ft. by 5 ft.; Reach 0 ft.; SQ swarm, aquatic, distraction, low-light vision; AL none; SV Fort +6, Ref +8, Will +2;
AP 0; Rep +0; Str 1, Dex 17, Con 12, Int 1, Wis 10, Cha 1.
Skills: Hide +8, Spot +5.
Feats: None.
Advancement: None.
Sentient Killer Bee Swarm
The killer bees in this swarm possess a hive mind. If dispersed, the bee swarm loses its intelligence (as individual
bees are nonintelligent).
Poison (Ex): Bite-Fortitude save (DC 14) negates; initial and secondary damage 1d3 Con.
Resistance to Massive Damage (Ex): A sentient killer bee swarm gains a +5 species bonus on Fortitude saves to negate the effects of massive damage.
Darkvision (Ex): A sentient killer bee swarm can see in the dark up to 60 feet. Darkvision is black and white only, but it is otherwise like normal sight, and the killer bees can function with no light at all.
Sentient Killer Bee Swarm: CR 5; Medium vermin (swarm of Fine vermin); HD 5d8; hp 22; Mas 10; Init +5; Spd fly 20 ft. (perfect); Defense 15, touch 15, flat-footed 10 (+5 Dex); BAB +3; Grap -; Atk swarm (3d6 plus poison, swarm); Full Atk swarm (3d6 plus poison, swarm); FS 5 ft. by 5 ft.; Reach 0 ft.; SQ swarm, sentience, distraction, poison, resistance to massive damage, darkvision 60 ft.; SV Fort +4, Ref +6, Will +2; AP 0; Rep +0; Str 1, Dex 20, Con 10, Int 10 (- when dispersed), Wis 12, Cha 2.
Skills: Hide +7, Intimidate +4, Listen +7, Move Silently +7, Spot +7.
Feats: None.
Advancement: None.
Shadowmoth Swarm
Vermin: A shadowmoth swarm is immune to mind-affecting attacks.
Resistance to Massive Damage (Ex): A shadowmoth swarm gains a +5 species bonus on Fortitude saves to negate the effects of massive damage.
Darkvision (Ex): A shadowmoth swarm can see in the dark up to 60 feet. Darkvision is black and white only, but it is otherwise like normal sight, and the shadowmoths can function with no light at all.
Shadowmoth Swarm: CR 1; Medium vermin (swarm of Fine vermin); HD 2d8; hp 9; Mas 10; Init +5; Spd 10 ft., fly 30 ft. (perfect); Defense 15, touch 15, flat-footed 10 (+5 Dex); BAB +1; Grap -; Atk swarm (1d6, swarm); Full Atk swarm (1d6, swarm); FS 5 ft. by 5 ft.; Reach 0 ft.; SQ swarm, vermin, distraction, resistance to massive damage, darkvision 60 ft.; AL none; SV Fort +3, Ref +8, Will +0; AP 0; Rep +0; Str 1, Dex 20, Con 10, Int 1, Wis 10, Cha 2.
Skills: Listen +5, Spot +5.
Feats: None.
Advancement: None.
Skeletal Rat Swarm
Undead: Skeletal rat swarms are immune to poison, sleep, paralysis, stunning, disease, necromantic effects, and mindaffecting effects. They are not subject to critical hits, nonlethal damage, ability damage, ability drain, energy drain, or effects of massive damage, or any effect requiring a Fortitude save unless the effect also works on objects or is harmless. They may be healed by application of negative energy (such as an inflict light wounds spell). The swarm is destroyed if reduced to 0 hit points or less.
Immunities: A skeletal rat swarm is immune to cold and takes only one-quarter damage from ballistic, piercing, or slashing weapons.
Darkvision (Ex): A skeletal rat swarm can see in the dark up to 60 feet. Darkvision is black and white only, but it is otherwise like normal sight, and the skeletal rats can function with no light at all.
Skeletal Rat Swarm: CR 2; Medium undead (swarm of Fine undead); HD 3d12; hp 19; Mas -; Init +1; Spd 20 ft.; Defense 13, touch 11, flat-footed 12 (+1 Dex, +2 natural); BAB +1; Grap -; Atk swarm (2d4, swarm); Full Atk swarm (2d4, swarm); FS 5 ft. by 5 ft.; Reach 0 ft.; SQ swarm, undead, immunities, distraction, darkvision 60 ft.; AL none; SV Fort +1, Ref +2, Will +3; AP 0; Rep +0; Str 3, Dex 12, Con -, Int -, Wis 10, Cha 1.
Skills: None.
Feats: None.
Advancement: None.
West Nile Mosquito Swarm
This cloud of mosquitos drains blood from its victims and also carries a deadly virus.
Vermin: A West Nile mosquito swarm is immune to mindaffecting attacks.
Disease (Ex): West Nile virus-bite. Fortitude save (DC 12) negates; incubation period 1d4 days; initial damage 1 Dex and 1 Con; secondary damage 1d2 Dex (temporary) and 1d2 Con (temporary or permanent).
Resistance to Massive Damage (Ex): A West Nile mosquito swarm gains a +5 species bonus on Fortitude saves to negate the effects of massive damage.
Darkvision (Ex): A West Nile mosquito swarm can see in the dark up to 60 feet. Darkvision is black and white only, but it is otherwise like normal sight, and the mosquitos can function with no light at all.
West Nile Mosquito Swarm: CR 1; Medium vermin (swarm of Fine vermin); HD 1d8; hp 4; Mas 10; Init +4; Spd fly 20 ft. (perfect); Defense 14, touch 14, flat-footed 10 (+4 Dex); BAB +0; Grap -; Atk swarm (1d4 plus disease, swarm); Full Atk swarm (1d4 plus disease, swarm); FS 5 ft. by 5 ft.; Reach 0 ft.; SQ swarm, vermin, distraction, disease, resistance to massive damage, darkvision 60 ft.; SV Fort +2, Ref +4, Will +1; AP 0; Rep +0; Str 1, Dex 18, Con 10, Int -, Wis 12, Cha 2.
Skills: Listen +6, Spot +6.
Feats: None.
Advancement: None.
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