A special container that can hold the invocation items, and only the invocation items. Has bag-of-holding-like properties (or else is an artifact bag of holding). It appears in some hard to reach place in the dungeon.

The quest leader either sometimes or always asks for the quest artifact back when you return with it, to replace the weird flavor in most quests that the leader is desperate to get the artifact back but is then completely fine with you adventuring off with it after retrieving it.

If you refuse to give them the artifact back, they turn hostile. If it’s a chance-based system, the chance might be dependent on your alignment record, so a character that has misbehaved is less likely to be found worthy of keeping the artifact. However, since you must have +20 alignment to enter the quest and get a massive amount of alignment from killing the nemesis, it’s questionable whether anyone’s alignment will ever be in a bad enough state to increase the chances. Luck has also been suggested as a variable that influences the chance, but most players will already have maxed their luck by the end of the quest.

In order to keep the player from just dodging the quest leader on their way out of the quest so that they can keep the artifact, various enforcement mechanisms have been proposed:

• Incentive-based; returning the artifact gives you +5 alignment record (and set to 0 if negative) and +3 to luck. Rewards should be better than the incentive of killing the quest leader to get the artifact back, or else penalties applied if you kill them (e.g. the artifact blasts you even though it’s your own quest artifact).
• Strict: you must show the artifact to the quest leader and have the quest marked completed in order for the invocation to work. Alternatively, the quest leader has the Bell of Opening and will only surrender it when you present the artifact, whether or not they demand it back. Or the quest nemesis has cursed the Bell and the leader will lift the curse after you show them the artifact.
• Delayed: you don’t have to go without the artifact forever, but the leader demands it back for some time so that they can fix whatever problem the artifact needed to solve. This could manifest as either a variable number of turns, or a requirement to go explore a certain number of new levels/area, before they’re done with it.

If you chat to the Oracle while carrying invocation artifacts (or possibly just after you’ve triggered the game flags for having acquired them at some point) she offers you a special consultation which helps show an unspoiled player the next step to take to complete the game, given what you have so far.

Priests get buffed effects from the invocation artifacts:

• The Bell of Opening opens things at range.
• The Candelabrum’s light is brighter (or “sunlight”) and affects things sensitive to light such as gremlins and vampires. The candles could also burn slower.
• The Book of the Dead either improves the power of turning undead, or makes it easier to raise the dead.

Ringing the charged Bell of Opening on the Astral Plane aggravates every monster.

When a magic trap shakes your pack violently, any bells you happen to be carrying get rung. For normal bells this doesn’t do much besides awaken monsters, but the charged Bell of Opening will be rung, do its usual ring effects, and lose a charge.

In variants or proposals where you can kill your quest leader to get the Bell of Opening, if you have permanently converted alignment already, killing your Quest leader does not give you a massive alignment penalty.

The Bell of Opening is carried by your quest leader, who gives it to you when you return to them with the quest artifact. This solves the problem of making a game unwinnable by permanently changing alignment, since you can also get it by killing the quest leader. Should the leader leave the level (by levelporting down, for example), they are considered derelict of duty and the player can start the quest.