An instance is a special area, typically a quest area, that generates a new copy of the location for each player or group that enters the area. Players cannot see other players in instanced areas unless it a group instanced area - in which case the group cannot see any other groups.
Instanced areas can take place in entirely new areas that cannot be accessed without the instance or in areas that are normally not instanced. Most non-quest boss instances will require the player to pay a specific sum of money or have an item in their inventory access the instance.
Examples of instanced areas include:
- Boss areas:
- Many quest areas:
- Floors in Dungeoneering
- Some after-quest bosses: Bork, Skeletal Horror, Phoenix Lair
- Some past tutorials: Learning the Ropes and Unstable Foundations
Most bosses have an instance option (sometimes called "custom session" or "custom encounter"), which may have an setup or entrance cost (coins or an item). Instances also share the requirements of the boss, and "hard mode" instances often have an additional requirement. The cost varies per instance and are shown below.
Most boss instances can be rejoined easily - simply use the "rejoin" option in the instance creation interface to re-enter the instance. If there is no one in the instance,The remaining duration of an instance can be extended by an hour by using the hourglass found in the HUD, costing the same as making a new instance (this is currently only available for God Wars Dungeon bosses). Exiting to the lobby or logging out in an instance will automatically remove you from the instance, placing you either at the entrance to the instance or the grave location, boss dependant.
Most bosses also have a practice mode available, which is toggleable from the instance creation interface. This mode makes all deaths inside the instance safe (including Hardcore Ironmen) - all items retained and no grave spawned - but the boss gives no experience, drops and the kill does not count toward Slayer or Soul Reaper tasks, nor is it added to the counter found in the Hero interface. Gear degrades as normal and consumed food, potions, ammo, runes and any other items are not refunded when leaving.
When the instance time runs out, a message says, "This arena has now expired and no further bosses will spawn." If the player is in the middle of a fight, the boss will not respawn after it is killed, and no further coins will be taken from the player's money pouch to renew the instance.
When beginning a practice session where possible, players do not have to pay to start the instance.
An onscreen timer will appear when the boss spawns and will stop upon its death, tracking the player's fastest time killing it. The timer, and consequently their fastest time, will not appear should there be more than a certain amount of players in the boss area at once: 
- Giant Mole - 1
- TzTok-Jad - 1
- Queen Black Dragon - 1
- Commander Zilyana - 1
- General Graardor - 1
- Kree'arra - 1
- K'ril Tsutsaroth - 1
- Har-Aken - 1
- Legiones - 2
- Araxxor - 2
- Kalphite King - 3
- Nex - 3
- Barrows: Rise of the Six - 4
- Vorago - 7
|Boss||Access location||Cost (reduced cost)[notes 1]||Grave location||Notes|
|Vorago||Attempt to enter the Borehole||1,000,000 (750,000)||Inside the Borehole graveyard||Hard mode only available in instance (no additional cost). Spawn speed selection not available.
After a kill in the instance, all participants in the battle will end up in the regular room, not instanced.
|Nex||Interact with the Prison Barrier||800,000 (600,000)||Inside the Ancient Prison lobby (requires 40 Zarosian kills or a set of ancient ceremonial robes)||Ashuelot Reis is present in the lobby inside the instance for using the bank. Lobbying in an instance will result in the player having to re-enter the room to use the barrier again. Nex will always start off with the Deflect Magic curse in an instance.|
|Kree'arra||Interact with the big door to the boss, inside the lobby within each faction's section (requires 40 killcount or a charged soulstone)||200,000 (150,000)||Inside the lobby within each faction's section (requires 40 killcount, or a charged soulstone)||Hard mode only available in instance (no additional cost)|
|Vindicta and Gorvek||Interact with the portal to the boss, inside the lobby within each faction's section (requires 40 killcount)||Free||Outside the entrance to the lobby within each faction's section||Challenge mode also available (no additional cost)|
|Araxxor/Araxxi||Interact with the webbing covering the entrance to the arena||200,000 (150,000)||Inside the Araxyte Hive graveyard||100% chance of Araxxor spawning in the style it is weak to based on mainhand weapon regardless if pheromone is in inventory or not. Spawn speed selection not available. Maximum players not available.|
|Legiones||Interact with the door to the respective Legio's laboratory||One Ascension keystone of the respective type ( Primus, Secundus, Tertius, Quartus, Quintus, Sextus) per fight[notes 2]||Outside the Legio's door or outside the Monastery, near Ocellus||Requires 95 Slayer. One keystone is required per fight. No practice mode available. Standard interface not used.|
|King Black Dragon||Interact with the artefact north of Edgeville monastery or go down the ladder at the Lava Maze entrance and interact with the artefact||50,000 (37,500)||Next to the artefact inside the non-instanced King Black Dragon lair||Aggressive poison spiders are at the Lava Maze artefact|
|Kalphite Queen||Interact with the hole down to the Queen inside the Kalphite Hive||100,000 (75,000)||Next to the rope inside the non-instanced Kalphite Queen lair||Aggressive Kalphite Guardians are at the instance creation location, making an instance difficult unless they're killed|
|Exiled Kalphite Queen||Interact with the hole down to the Queen inside the Exiled Kalphite Hive||100,000 (75,000)||Next to the entrance inside the non-instanced Exiled Kalphite Queen lair||Aggressive exiled kalphite guardians and marauders are at the instance creation location, making an instance difficult unless they're killed|
|Corporeal Beast||Select Custom-session from the right-click menu of the final passage to the Beast||300,000 (225,000)||The instance has no lobby area - you enter directly to the arena. The Beast spawns in the centre of the arena (rather than the east side).|
|Dagannoth Kings||Interact with the hole at the end of the Waterbirth Island Dungeon||150,000 (112,500)||Next to the entrance inside the non-instanced Dagannoth Kings lair|
|Barrows: Rise of the Six||Interact with the well just north of the Barrows||1 Barrows totem per fight[notes 3]||Inside the graveyard accessed from the well||Maximum players and spawn speed selection not available.|
|Giant Mole||Interact with the plant in Falador Park||Free||Near the plant in the park||No non-instanced version available. Spawn speed selection not available. Hard mode available.|
|Kalphite King||Interact with the hole inside the Exiled Kalphite Hive||Free||Inside the Exiled Kalphite Hive, north of the entrance in the "graveyard"||If players leave instance and attempt to enter in a short period of time, they will be unable to interact with the hole for a while.|
|Queen Black Dragon||Interact with the portal in the deepest part of the Grotworm Lair||Free||Outside the portal||Requires 60 Summoning. No non-instanced version available. Use the Investigate option on the portal and proceed through the dialogue to access the interface (for practice mode); using the Pass-through option gives no interface and goes straight to the fight.|
- ^ Purchasing the Instance cost Soul Reaper perk reduces the coin cost of an instance by 25%.
- ^ Each kill requires one key. The instance does not need to be left to respawn the boss.
- ^ Each kill requires one totem. Instance needs to be recreated for each kill.
Instance shard worldsEdit
Instance shard worlds are special worlds (or servers) that have been sharded off from the rest of the servers. They cannot be accessed via the world select screen. Currently, only the TzHaar Fight Pit, Flash Powder Factory, Crucible, Burthorpe Games Room, Big Chinchompa, Cabbage Facepunch Bonanza and all Clan Citadels are located on instance shard worlds.