Arcane Device

The essence of artifice is the creation of wondrous devices that utilize or manipulate the magic which permeates the world, and the ability to create arcane devices is a testament to this principal.  Such devices highlight the artificer's ability to prepare in advance and whether thrown as a grenade or activated for personal use, this esoteric invention offers significant versatility to a tinkerer of the arcane.

The artificer assembles a device that stores another spell and which is small enough to carry or throw.  The device itself offers no indication of what it will do when triggered unless its creator marked it as such, but using detect magic reveals abjuration magic and the identify spell identifies the stored spell.  The device can be disarmed by using thief's or tinker's tools with a DC of 13 plus the spell level, and a failed disarm attempt triggers the effect immediately.  If attacked, the device has 10 hit points, an AC of 15, and activates if destroyed.  If dispelled the device becomes useless without triggering its stored effect.

Once triggered, the stored spell is cast at the same level as Arcane Device, affecting an area centered on the device or targeting the creature that activated it.  Any saving throws against the stored spell have a DC of 13 plus the spell level, and an effect with a duration lasts for the full duration regardless of whether or not it normally requires concentration.  However, an effect with a duration ends immediately if the device is subsequently destroyed, disarmed, or dispelled.

There are two distinct types of Arcane Device that can be created.

Arcane Grenade
An arcane grenade stores one of the following spells: burning hands, color spray, faerie fire, fog cloud, grease, shatter, or web.  The stored spell is triggered when the grenade is thrown as an Action, and the area of effect is a 10-foot radius centered on where the grenade lands, regardless of the spell’s normal area of effect.

Throwing an arcane grenade is resolved as a throwing attack with an improvised weapon targeting a location (AC 10), and which has a range of 15/40. If the attack roll fails, roll 1d8 to determine direction and 1d4-1 (minimum of 1) to determine distance in squares (5 ft.) that the grenade deviates from the intended target location.  Alternatively, an arcane grenade can be placed in a stationary location and armed with the snare spell. In this case, when Snare is triggered, it activates the grenade instead of Snare’s normal effects.

Arcane Battery
An arcane battery can store any artificer spell up to the level at which Arcane Device is cast, provided the spell has a casting time of one action and targets a single creature with a range of either self or touch. When activated using a Bonus Action, an arcane battery casts the stored spell, targeting the creature who activated it.  If the spell has multiple options, then the selection must be made when the arcane battery is created.  For example, if used to store alter self, the choice of Aquatic Adaptation, Change Appearance, or Natural Weapons must be made, and even the specific appearance or specific natural weapon must also be chosen.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the stored spell is cast at the higher level and new options become available to arcane batteries.