pKill Node

pKill is the simplest life-cycle node: as soon as a particle crosses its region, it is instantly removed from the system (as if its Lifespan had been reached).

Unlike a natural Lifespan, pKill gives you spatial control - particles die where you want, not when you want. Very useful for performance in scenes with particles that would otherwise travel forever.

• Effects Library: Tools > Particles > pKill
• Quick add: right-click in the Node Editor → Add Tool > Particles > pKill

• Particle Input (orange) - output of a particle node.
• Region Input (green/magenta) - optional. A 2D bitmap or 3D mesh that defines the destruction area. Essential to control precisely where particles die.

Scene boundaries:
pEmitter → pForces → pKill ← Shape 3D (cube = visible scene)
                    (Region = Inside Inverse)
         → pRender
(particles leaving the cube are killed)

Cleanup below the floor:
pEmitter → pDirectionalForce (gravity) → pKill ← Shape 3D (plane at the bottom)
                                       → pRender
(particles falling below the floor disappear)

Stylized vanishing zone:
pEmitter → pKill ← Shape 3D (magic effect sphere)
(particles entering the sphere are destroyed = a vaporizing effect)

pKill has no main parameter. All the setup happens in the tabs shared by particle nodes:

Region tab

Defines the area where particles are killed. Options: All (everywhere), Bitmap, Mesh, Cube, Sphere, Line, Rectangle. With an Inside / Inside Inverse toggle to kill inside or outside the area.

Conditions tab

Targets certain Sets only, with a min/max age and a kill probability (allows partial kills).

Start / End Age

Kills only particles within a given age range. For example, it lets you leave young particles alone and only kill the old ones.

Probability

Percentage of particles killed in the region. 1.0 = all, 0.5 = a random half. A "fuzzy" kill rather than a binary one.

• Scene boundaries - a Shape 3D cube enclosing the visible scene + Region Inside Inverse = every off-frame particle dies (massive optimization).
• Cleanup below the floor - a Shape 3D plane at negative Y = particles below the floor are removed after an imperfect pBounce.
• Performance optimization - limits the number of live particles at any moment. A pKill over a large area = a drastic drop in computation cost.
• Narrative vanishing zone - particles touching a portal, a shield or an aura = instant vaporization (stylized effect).
• Stylized fade-out - pKill with Probability 0.1 = some particles gradually die in an area, a natural thinning effect.
• Limiting the reach of an explosion - a kill sphere X units from the center = debris does not travel too far.

• Always place pKill at the end of the chain - right before pRender, after all the forces. Avoid killing particles that still had to be transformed.
• Region Inside Inverse for boundaries - kill everything outside the useful area. The standard way to confine a system to a scene.
• Instant performance - on a heavy comp, adding a simple pKill can cut render time by 2-3x by removing invisible particles.
• Probability for a gradual kill - better than a binary kill for some narratives (gradual dissipation in an area).
• Combine with pChangeStyle - for a "fade out before death" effect, pChangeStyle (size/alpha reduction), then pKill.
• No effect without a Region - if the Region tab = All, every particle dies immediately. Always set a precise area.
• For a classic Lifespan (particles dying of old age), stick to the pEmitter Lifespan parameter. pKill is for spatial/conditional control.