Chrono Prism

Chrono Prism

Wondrous Item

Legendary Requires Attunement

This shimmering gemstone, the size of a human fist, pulses with a soft light. The Chrono Prism was created by Alex Cogswell, and was based on a similar object that he had used while being a member of the Fraternity of Orders. The gem's magic allows it to be attuned to multiple beings, forging a bond of mutual agreement between them.
Shared Attunement: To attune to the prism, a minimum of 4 creatures must meditate near it for the duration of a short rest. Only the member that holds the gem is required to expend an attunement slot; the other members become attuned to it without expending an attunement slot. All creatures attuned to this gem can sense when it’s being used. A creature attuned to the device can use any of its properties, but only if all other creatures attuned to it agree to allow it and are conscious.
Shared Burden: When the member that holds the gem takes a particularly devastating blow, the overwhelming force of the impact can sometimes be felt amongst all other attuned members. Up to half of the damage may be dealt to all other attuned members, up to the DM’s discretion.
This gem has 10 charges, and regains 1d6+1 charges every dawn.
Unified Ward (4 charges): As an action, use the gem’s power to cast the Wall of Force spell, though you may only choose between a hemispherical dome or a sphere. The member who cast this spell must still maintain concentration on it.
Harmony Surge (3 charges): As an action, tap into the gem’s power to bestow every attuned member including yourself with 1d20+5 temporary hitpoints. This effect ends when any of the attuned members loses all of their temporary hitpoints.
Temporal Stasis (2 charges): The attuned members can choose to use the gem to nearly stop the passage of time. For all external observers, only a second passes, but for the attuned members, time slows down dramatically, allowing them ten minutes to discuss, strategize, or deliberate.
Conjoined Strategy (1 charge): At the start of combat, if two or more attuned members are present, they can quickly strategize, allowing one member to swap their initiative score with another (after bonuses are applied).
Shared Arcana (X charges): An attuned caster can use a spell slot from another attuned member to cast a spell they know or have prepared. This feature uses X charges, where X is half the spells level rounded down (minimum of 1 charge).