Corrosive heart

The corrosive heart is an artificial body part added by the Anomaly DLC that acts as a replacement for a ghoul's heart. It gives ghoul the ability to spit acid at the expense of lower part efficiency and thus blood pumping.

Acquisition

Corrosive hearts can be crafted at a bioferrite shaper once the ghoul enhancements research project has been completed. Note that this research requires dark study to unlock. Each requires 20 Bioferrite, 1 Component, 13,200 ticks (3.67 mins) of work modified by the general labor speed of the crafter, and a crafting skill of 4.

It can sometimes spawn on hostile ghouls,^{[Starter colonist?]} however they cannot be harvested from them.

Summary

Use the corrosive heart to spray acid a short distance. The heart pumps the corrosive fluid through a surgically implanted duct, allowing the ghoul to spew it from their mouth at high velocity.
— Corrosive spray description

The corrosive heart is a ghoul exclusive body part. Corrosive hearts have an 85% part efficiency, or a −15% reduction compared to a healthy organic heart. This results in −15% loss to Blood Pumping.

The reduction to Blood Pumping lowers move speed by a total −6% and Consciousness by −3%. The reduction of Consciousness in turn reduces Manipulation, Talking, and Eating. For a full breakdown of the affected stats, see those pages.

Pawns with the heart installed have access to the "Corrosive spray" ability while drafted. The spray must be manually initiated by the player through use of a gizmo available while the ghoul is drafted and selected. Colonist ghouls will never independently use the spray.^[Verify] It is currently unknown whether NPC ghouls will use the ability.^{[Detail needed]}

Spits a fast-moving corrosive fluid projectile in a 3x3 area around the target. This does 30 damage to buildings and items, and creates a harmless "spent acid" filth on each affected tile. Creatures in the affected area suffer a 30 damage burn (possibly spread over multiple body parts), but suffer no persistent damage over time. The attack has an AP of 80%^{[Armor type?]} and a stopping power of 1.

Target: Pawn or Location
Range: 11.9
Warmup Time: 15 ticks (0.25 secs)
Cooldown: 5,000 ticks (1.39 mins).

Installation

The corrosive heart can only be installed in ghouls. Note that despite the description noting pain as the reason it cannot be installed in other pawns, methods of pain nullification such as painstoppers do not allow the heart's installation into other pawns.

Installing the part requires 2,500 ticks (41.67 secs) of work. It doesn't anesthetize the ghoul, requires no medicine, cannot fail, but requires medical skill of 4.

Removing the part requires ? of work, ?x medicine of ? quality or better, and has no Medical skill requirements.^[Verify?]

Unlike most operation, installing the heart cannot fail.

Analysis

The attack itself is almost identical to Acid spray but the warm up and cooldown times are different.

Acid damage is great for inflicting pain upon pawns, as chemical burn inflict much more pain than bruises or cuts. A corrosive spray followed by a few punches is enough to down most pawns from pain shock. Consider having a few ghouls with this ability to deal with escaping prisoners, entities, or to down fleshbeasts, noctols, or gorehulks for capture.

However, this heart also reduce move speed by the indirect effect of conciousness, causing your ghoul to be even slower.

Heart	Cost	Blood Pumping¹	Side Effects	Ability	Market Value
Prosthetic heart	25+ 4	80%			230
Heart	-	100%			1,200
Bionic heart	15+ 4	125%			1,030
Corrosive heart	20+ 1	85%		Corrosive spray	95
Adrenal heart	20+ 1	100%	Hunger rate: +15%	Ghoul frenzy	95
Metalblood heart	20+ 1	100%	Move speed: −0.20	Metalblood injection	95