Spawn
From WoWWiki
Spawn describes the process of a mob entering the game world. This can happen due to various causes - most mobs killed by players return after a certain time (this is called respawn), other mobs come into existence when their preconditions are met (e.g. certain attacking mobs on a patrol quest). Depleted Resource Nodes also respawn after some time.
When players first enter a new area, and some time ago other players killed many mobs (e.g. to fulfill a quest), the new arrivals may easily be surprised by respawns. This effect is alleviated by the fact that right after a respawn, mobs stand still and do not attack for about 5 seconds. This gives players enough time to move out of the aggro radius, if they react quickly.
Respawn time
Most normal mobs usually are on a 15 minute respawn timer. This may be different depending on area and mob type. Additionally, if an area is heavily farmed, and the mobs are killed very quickly right after they spawn, the game may switch to a fast respawn mode for that area, which means that mobs and resource nodes return much more quickly, usually within one minute.
The following is an overview of mob types and their usual respawn timers:
- Standard:
- 15 min
- Named mobs:
- Normal named mobs may either be on the regular respawn timer, or they may be rare mobs, with timers of several hours or more (e.g. Broken Tooth).
- Instance trash mobs:
- In instances, trash mobs usually are on a 2 hour respawn timer. There may be exceptions, sometimes instance designer use short respawn timers to create an extra challenge (e.g. Ancient Core Hounds). In raid instances, trash mobs are usually "bound" to a boss, and after that boss is killed, the trash does not spawn any more.
- Instance bosses:
- Instance bosses do not have a respawn timer at all. They only return on instance reset.
Note: while actions like skinning causes corpses to disappear, there is no evidence that this makes the mob respawn faster.
