Elemental Essence Shard (Fire)
Wondrous item, spellcasting focus, rare (requires attunement by a sorcerer)
- Weight: 1.0 lbs.
This crackling crystal contains the essence of an elemental plane. As an action, you can attach the shard to a Tiny object (such as a weapon or a piece of jewelry) or detach it. It falls off if your attunement to it ends. You can use the shard as a spellcasting focus while you hold or wear it.
When you use a Metamagic option on a spell while you are holding or wearing the shard, you can use the following property:
Property
One target of the spell that you can see catches fire. The burning target takes dice:2d10|noform|noparens|avg (2d10) fire damage at the start of its next turn, and then the flames go out.
Source: Tasha’s Cauldron of Everything p. 127