Firebats

Firebats is a Fire spell used by Witch Doctors in Diablo III.

In-game
Channels a swarm of fiery bats, hitting all enemies in a 20 yard, 45 degree cone in front of the Witch Doctor for Fire damage per tick. This counts as a torrent, bypassing most obstacles (including Waller barriers), only stopping if it hits a solid wall.

Runes:

 * Dire Bats: Instead of the swarm, summon larger bats that deal 500% damage as Fire each. Distance is increased to 40 yards, and the bats pierce through enemies and obstacles.
 * Vampire Bats: Damage type changes to Physical. Removes the channeling cost, but the initial Mana cost increases to 250.
 * Plague Bats: Changes damage type to Poison. As the spell is channeled, the damage grows by +25% per tick, up to 720% (that is, +50%).
 * Hungry Bats: instead of the swarm, launches homing bats (3 per tick) that seek enemies within 20 yards and hit them for 750% damage as Fire each.
 * Cloud of Bats: Instead of the cone, creates a swirl of bats that damages enemies within 15 yards of the Witch Doctor for 425% damage as Fire per tick. The damage of the bats increases by +20% every second, up to a maximum of +100% (850% damage as Fire per tick), but is reset if the channeling is interrupted.

Non-rune enhancements:

 * Taeguk (Legendary Gem): increases damage done by 2% per tick (+0.04% per rank) and armor by 2% per tick (rank 25 bonus), stacking up to 10 times.
 * Bakuli Jungle Wraps (Legendary Belt): Firebats deal 250-300% increased damage against enemies affected by Locust Swarm and/or Piranhas.
 * Coils of the First Spider (Legendary Bracers): while channeling Firebats, gain 60000-80000 Life per Hit and take 30% reduced damage.
 * Staff of Chiroptera (Legendary Staff): Firebats deal 125-150% more damage, attack twice as fast and cost 75% less Mana.
 * Mantle of Channeling (Legendary Pauldrons): while channeling Firebats, increases damage done by 20-25% and reduces damage taken by 25%.
 * Helltooth Harness Set (Set Bonus for 2 items): damaging enemies with Firebats will apply Necrosis, slowing enemies by 60% and inflicting 3000% damage per tick for 10 seconds. Elemental Damage type is chosen from the highest skill bonus of the character.
 * Helltooth Harness Set (Set Bonus for 6 items): after casting Wall of Death, gain +17500% increased damage for 15 seconds for Firebats.
 * Spirit of Arachyr Set (Set Bonus for 6 items): increases damage by 17500%.
 * Zunimassa's Haunt Set (Set Bonus for 6 pieces): pets deal 15000% more damage to enemies damaged by Firebats for 8 seconds, the effect does not stack.

Trivia

 * Firebats are terran flamethrower heavy infantry in the StarCraft universe.