Difference between revisions of "NPC"

Revision as of 18:52, 18 October 2020

NPC is an acronym for Non-Player Character. In EverQuest, like many RPGs, characters are living, unliving, or otherwise animated entities which talk, interact, fight, sell, bank, or train players. NPCs are controlled by server-side scripts (or several commands in the case of pets) while in contrast player characters (PCs) are avatars controlled by players.

NPC behavior on p99 is not externally documented but over the years veteran players have observed consistent patterns which usually make NPCs very predictable, once these patterns are understood.

Spawn

The life of an NPC begins when they spawn. Every time an NPC spawns, it has a cause:

• Simulated Respawn, a.k.a. Earthquake, patch day resets or other forms of server reset
• Respawn - usually occurs a fixed period of time after the NPC's last death/despawn. Many bosses and important NPCs have a variable respawn time known as a window.
• Summon (pets)
• Kill trigger (e.g. The Avatar of War)
• Quest trigger (e.g. Vorash)
• Aggro trigger (e.g. Vindi's pets)
• In-game time (e.g. undead or animals in Kithicor Forest)
• GM ability

Despawn/Death

The life of an NPC ends with a despawn or death. There are less causes for despawn:

• Death - semantically this is not a despawn but it's effectively the same except it leaves a corpse.
• Simulated Respawn a.k.a. Earthquake (a type of server reset) most NPCs respawn
• Quest trigger (e.g. any Plane of Sky quest gear turn-in NPC, and many examples in epic quests)
• In-game time (e.g. the undead and animals in Kithicor Forest or Mammoth in Surefall)
• No owner - pets summoned by PCs will immediately despawn when their owner dies, zones, or receives buffs like Invisibility
• No aggro - pets summoned by NPCs without owners and certain triggered-spawn NPCs will despawn when they don't have an aggro table and/or have been alive for a minimum period of time

Spells

Many NPCs which are of a class capable of casting spells will cast spells.

NPCs seem to have limited mana, but it regenerates much more quickly than players, especially when NPCs are out of combat (as does their health). Mana Sieve or Theft of Thought are very useful for preventing an NPC from casting spells, but may require more repeated applications than you might expect.

Like players, NPCs have a fixed number and selection of spells appropriate to their class and level. An NPC Wizard, Druid, or Shaman may be capable of casting Gate, but a Shadow Knight cannot. Most NPCs of a given class and level can be expected to have the same set of memorized spells, but there are exceptions of customized sets, especially among bosses or raid targets.

While aggroed, the NPC will, at random server ticks, attempt to cast spells if they are in line of sight of their aggro target. NPCs are more likely to cast movement restricting spells (like Root or Snare) on distant targets they are chasing down compared to melee range targets, they might nuke more often as well. NPCs with stuns, mez, or fear spells may cast them on secondary targets instead rather than their aggro target. NPCs with targeted AOE spells will cast them just like regular nukes and make no distinction about targetting groups of players with those spells. NPCs with PBAOE spells will not begin to cast them unless their primary aggro target is in range of it.

NPCs never attempt to interrupt themselves from casting a spell, even if a player moves out of range, dies or FDs. They will wait until the casting timer is completed and cast on the corpse if available. If an NPC casts a spell on an FDed player in this way or by AOE, then the FD is broken and the NPC will immediately re-aggro if they were aggroed before.

NPC AOEs will not land on friendly NPC targets but will land on players regardless of faction.

NPCs will buff themselves and nearby social NPCs with memorized spells if available. It seems that they begin to cast a buff on a random chance basis on server ticks. They seem to check if they already have a buff before casting it again to save mana. NPCs will heal and summon pets in the same manner. Heals may also be cast in combat, but only if the target is themselves or a social NPC and is damaged below about 30-40% HP. All beneficial spells cast by NPCs do not check line of sight, but do check range.

Procs

Like players, NPCs can proc effects from their melee attacks. The chances of procs is presumably affected by DEX, might be reduced against players with Disciplines like Evasive and Whirlwind, and will never occur on absorbed attacks (those mitigated by Runes, Rampage, Divine Aura, etc.).

Procs may come from weapons, buffs (like Vampiric Curse or from innate procs (like Ghoul Root, Deadly Lifetap or Efreeti Fire).

Special abilities

Special abilities are often confused with procs. These are very similar to skills like Harm Touch, they often have some limited range beyond melee range (or can be zone-wide in the case of Cazic Touch). All of these abilities have a cooldown, and probably don't consume mana (or very much mana). Like spells, NPCs use these abilities at random server ticks after the cooldown has expired, but that random chance each tick seems to be much higher compared to spells, so they usually use them more quickly. Some examples:

• Summon
• Enrage
• Rampage
• Cazic Touch
• Dragon Roar
• DryBoneFireBurst
• EarthElementalAttack
• Specter Lifetap
• WhirlBolt
• Most dragon AOEs

If an NPC can cast something many times in rapid succession, then it's a proc. If they can cast it while chasing a player and not quite in melee range, then it's not a proc.

Perma-root

Some NPCs will never move from where they spawn, and cannot be pushed or pulled to a more advantageous location. Most of these are Velious boss dragons like Yelinak, Temple of Veeshan inhabitants and Tunare. Perma-rooted NPCs do not have the same aggro behavior as regularly rooted NPCs, and may attack further targets than the closest tank.

Aggro

See main article: Aggro

Un-aggroed Behavior

Before an NPC is aggroed, it will generally display one of three behaviors:

• Patrol - These NPCs patrol (pat for short) between fixed locations in a fixed order. There are no randomly pathing NPCs in classic EverQuest. All NPCs have fixed patrols, though some patrols may be so long and complex that they may seem random. If you observe an NPC long enough, you will eventually discover a repeating pattern.
• Static - These NPCs simply stand where they spawn and do not move until aggroed.
• Scripted - A few NPCs follow more complex scripted behaviors, generally in response to quests or dialog.

Vendor

See main article: Vendor

Banker

See main article: Banker