Projectile

Projectile

Tooltip

A Projectile is a moving Attack or Spell that usually impacts with targets when it hits them.

When a group of multiple Projectiles is fired from the same source at the same time, only one Projectile in the group can hit each target unless otherwise specified.

Projectiles are entities created by attack and spells that move along a trajectory and can hit other entities. They typically travel in a straight line from point A to point B.

General Mechanics

This section outlines the rules governing projectile behavior and interactions with other mechanics and entities.

Trajectory

By default, Projectiles will travel in a straight line from point A to point B in the direction of the cursor.

A projectile is destroyed when:

• It reaches its destination.
• It travels the maximum distance. (By default, 150 units in Path of Exile 1) Mark_GGG (July 19, 2016). "Mechanical Questions Thread". Official Path of Exile Forums. Retrieved January 4, 2024.
• Its duration ends.
• It collides with an entity, terrain or walls.

Different trajectories exist in some skills:

• Erratic: projectiles change their direction constantly in a random direction. Spark
• Homing projectiles: projectiles that can change their direction towards enemies. (see the Path of Exile 1 skill gem, Soulrend)

Most projectiles travel through the air. However, some travel along the ground. Projectiles that travel along the ground are constricted to travel only through "walkable" path, they also cannot be fired up or down cliffs or ledges, and will instead collide with the edge.

Certain skills have a "ground-targeted" aim, firing projectiles at the ground near the player's cursor. Examples

• Concoction skills
• Grenade skills

A subset of these "ground-targeted" skills fire their projectiles skyward, landing at the target location instead. These projectiles cannot collide with entities. Examples

• Rain of Arrows
• Tornado Shot

Speed and duration

Different projectiles have a base speed, which can vary depending on the skill and can be increased by other sources, such as modifiers, passive skills and support gems. Such as Acceleration or Deceleration

• Projectile lifespan is determined by a fixed duration, which is hidden and cannot be modified unless explicitly stated.
• A faster projectile will travel farther in its lifespan.

Interactions

Additional to dealing damage to enemies, projectiles can be influenced by other mechanics

Additional Projectiles

Several sources grant skills additional projectiles, enhancing their effectiveness and AoE.

• Some skills may modify the trajectory and behavior of the additional projectiles.
  • For example: Eye of Winter causes any additional projectile to be fired in a circle at the end of the main projectile.

Patterns

When using a skill that fires multiple projectiles, they can be fired in patterns:

• Cone: The default pattern for a skill that only has additional projectiles without a specific pattern.
  • The cone angle narrows as the aiming distance increases.
• Spiral: will fire projectiles sequentially from right to left in a circle around the user.
• Circle: will fire projectiles around the user at fixed angles based on the number of projectiles, simultaneously.

Collision

When a projectile collides with an enemy or another entity, it either ends or continues based on one of the projectile behaviors described below.

If multiple projectiles are fired simultaneously, only one of them can collide with the same target. unless otherwise stated. For example Freezing Shards.

This does not apply to projectiles fired in sequence, allowing them to hit the same target.

Behaviors

• Pierce: Allows projectiles to continue their trajectory after hitting an entity on their path.
  • Piercing can occur up to N times.
• Chain: Redirects a single projectile to the nearest target within chain range that has not been hit by other projectiles from the same group.
  • Chaining can occur up to N times per projectile.
  • Projectiles supported by Ricochet have a chance to chain from walls and terrain.
• Fork: Causes projectiles to create two copies upon hitting a target.
  • These copies are fired at a fixed angle from the target hit by the original projectile.
• Bounce: Allows projectiles to bounce from walls or terrain in a random direction. Not to be confused with Chain, which requires a target within chain range.
• AOE: Some skills throw projectiles that trigger their effects on an area of effect when they are destroyed or collide with entities.

Behavior priority and Interactions

Whenever a projectile collides, it will attempt each of its remaining behaviors

• Projectile behaviors occur in the following order, if applicable:

1. Pierce
2. Fork
3. Chain

For example:

• A projectile first pierces N targets.
  • If a projectile can pierce indefinitely, further behaviors will never activate.
  • Terrain cannot be pierced.
• The next target on its path causes the projectile to fork into two projectiles.
• The forked projectiles then chain N times until no valid targets remain or chaining is exhausted.

Different behaviors cannot occur simultaneously; the priority order determines how they occur.

Gems

A list of gems with the Projectile gem tag:

Skill gems

Gem	Tier
Spear Throw	0
Escape Shot	1
Poisonburst Arrow	1
Spark	1
Armour Piercing Rounds	1
Explosive Grenade	1
Falling Thunder	1
Fragmentation Rounds	1
Lightning Arrow	1
Lightning Rod	1
Permafrost Bolts	1
File:Lightning Spear inventory icon.pngLightning Spear	3
Ember Fusillade	3
Essence Drain	3
Frostbolt	3
High Velocity Rounds	3
Incendiary Shot	3
Snipe	3
Staggering Palm	3
Stormcaller Arrow	3
Vine Arrow	3
File:Storm Lance inventory icon.pngStorm Lance	5
Bonestorm	5
Electrocuting Arrow	5
Flash Grenade	5
Freezing Salvo	5
Galvanic Shards	5
Gas Grenade	5
Ice Shards	5
Molten Blast	5
Rapid Shot	5
Toxic Growth	5
Gas Arrow	7
File:Glacial Lance inventory icon.pngGlacial Lance	7
Explosive Shot	7
Glacial Bolt	7
Ripwire Ballista	7
Voltaic Grenade	7
Rain of Arrows	9
Dark Effigy	9
Fireball	9
Artillery Ballista	9
Detonating Arrow	9
Ice Shot	9
Oil Grenade	9
Stormblast Bolts	9
File:Whirlwind Lance inventory icon.pngWhirlwind Lance	11
Ball Lightning	11
Hailstorm Rounds	11
Shockburst Rounds	11
Shockchain Arrow	11
Tornado Shot	11
Eye of Winter	13
Cluster Grenade	13
Magnetic Salvo	13
Plasma Blast	13
Siege Cascade	13
Spiral Volley	13

Spirit gems

Gem	Tier

Support gems

Gem	Tier
Acceleration	1
Chain	1
Deceleration	1
Pierce	1
File:Retreat inventory icon.pngRetreat	1
Scattershot	1
Ricochet	2
File:Stormchain inventory icon.pngStormchain	2
File:Volt inventory icon.pngVolt	2
File:Freezefork inventory icon.pngFreezefork	2
File:Flamepierce inventory icon.pngFlamepierce	2
File:Alignment inventory icon.pngAlignment	3
File:Caltrops inventory icon.pngCaltrops	3
File:Charged Shots inventory icon.pngCharged Shots	3
Fork	3
File:Gambleshot inventory icon.pngGambleshot	3
File:Salvo inventory icon.pngSalvo	3
File:Spectral Volley inventory icon.pngSpectral Volley	3
Wildshards	3
File:Volcanic Eruption inventory icon.pngVolcanic Eruption	3

Version history

Version	Changes
0.1.0	Introduced to the game.