"Thunderhead" Heavy Autocannon

"A peculiar but devastating weapon. The slow rate of fire is made up for by heavy damage, delivered with glee by the belt-fed .50-caliber tungsten rounds. The Thunderhead is a somber weapon for the sophisticated executioner, delivering death as inexorably as the passage of time itself."

- Item Description

About
The "Thunderhead" Heavy Autocannon is an unlockable primary weapon for the Gunner. It is an oversized light machine gun with two massive barrels extending outwards which fire in sequence. The weapon is loaded by a huge ammo box.

The Autocannon fires explosive rounds which detonate upon hitting the world or a target. Enemies hit directly by rounds take both the damage of the bullet and the explosive damage at once. The rounds fired start out with a sluggish fire rate, but this can build up over time the longer the trigger is held.

The weapon is incapable of dealing friendly fire to teammates.

Understanding the Weapon

 * Damage is how much damage is dealt upon direct impact of the shot.
 * Area Damage is how much damage is dealt in addition to the direct damage within the damage radius around the impact.
 * Top Rate of Fire is the max rate of how quickly shots can be fired after sustained firing.

Rate of Fire Mechanics

 * The Autocannon has two hidden stats regarding rate of fire, which is its Starting Rate of Fire and Rate of Fire Scaling. They play an important role in determining how quickly max rate of fire bonuses are applied, and can be changed depending on which modifications/overclocks are taken.
 * Starting Rate of Fire default is 3.4
 * This determines how quickly shots are initially fired as its rate of fire starts to ramp up.
 * Rate of Fire Scaling default is 0.4
 * This is the coefficient of the exponential function that is used during the rate of fire rampup. The Autocannon's initial rate of fire continues to be scaled until the top rate of fire has been reached, which would then allow max rate of fire bonuses to be applied.


 * Modifications/Overclocks that affect Rate of Fire:
 * Improved Gas System
 * +0.3 Starting Rate of Fire
 * +2 Top Rate of Fire
 * Lighter Barrel Assembly
 * +0.6 Starting Rate of Fire
 * x1.5 Rate of Fire Scaling
 * Supercharged Feed Mechanism
 * +0.3 Starting Rate of Fire
 * +2.0 Top Rate of Fire
 * Big Bertha
 * -1.5 Top Rate of Fire
 * Combat Mobility
 * x1.5 Rate of Fire Scaling
 * +0.9 Starting Rate of Fire
 * Rate of Fire Formula
 * Let S be the Starting Rate of Fire
 * Let C be the Rate of Fire Scaling
 * Let M be the Max Rate of Fire
 * Let t represent the amount of seconds that has elapsed since the Fire button has been held down.
 * The Rate of Fire at any given time, t, can be represented as such:
 * \[R(t) = \min(S*e^{Ct}, M)\]
 * Such that when enough time has elapsed and \[S * e ^{Ct} \ge M\], time is no longer a factor in the Rate of Fire. At this point, the "Max Rate of Fire" Bonuses should kick in.

Suppressive Fire
Suppressive Fire inflicts 50% Fear to all enemies within a 1m radius of where bullets impact either enemies or terrain. Most of the small-to-medium creatures will have Fear inflicted on them by this upgrade. It is important to note that the radius of Suppressive Fire does NOT increase with any mods or Overclocks that affect the Damage Radius.

Neurotoxin Payload
Neurotoxin Payload is an Unstable Overclock. It grants all shots a 50% chance to inflict Neurotoxin onto an enemy. When an enemy is affected by Neurotoxin, they will take 12 Poison damage every 0.75 - 1.25 seconds for 10 seconds, as well as having their movement speed reduced by x0.7. Hitting an enemy who is already affected by Neurotoxin with another round which inflicts the debuff will reset its timer.

Mastery
Each modification that is purchased advances a mastery bar by one unit.

Mastery unlocks:
 * Three modifications – First Stripe Weapon Paintjob Icon_Skin_First_Stripe.png
 * Seven modifications – Deepcore Weapon Paintjob Icon_Skin_Deepcore.png
 * All (14) modifications – The Company Special Weapon Paintjob Icon_Skin_The_Company_Special.png

Skins
Full gallery of skins can be seen at Weapon Skins.

Trivia

 * Mission Control's dialogue upon completing the Weapon License Assignment for the Autocannon reads as follows:
 * "Good work. Management believes you're ready to handle our Heavy Autocannon, the "Thunderhead"... Be mindful not to blow off your own legs with it. This thing has a proper kick to it."
 * In older versions of the game the Powered Minigun also fed from a large ammo drum which needed to be reloaded, on top of its overheating issues. This was changed in Update 11: Dead and Gun to the current system where the Minigun feeds from a single drum and does not reload. It is likely that the Minigun's older reloading system influenced the Autocannon's design when it was added to the game a few months later in Update 19: Guns! Lots of Guns!

Cañón automático pesado "Thunderhead"