5e magic Item: The Wondermakers Key

The Wondermaker’s Key

Wondrous Item, Legendary ( Requires Attunement by an Artificer)

The Wondermaker’s Key is a key created by a long-forgotten master artificer. The Wondermakers Key is tied to a specific demi-plane called The Wondermakers Workshop.

Quiescent. The Wondermaker’s Key grants the following benefits in it’s Quiescent state.

The Wondermaker’s Key allows an attuned artificer to use the key as a spellcasting focus by transforming it into a +3 toolkit of the artificer’s choice.
The attuned artificer can cast Mend without using a spell slot.
The Wondermaker’s Key gives one additional temporary attunement to an uncommon or rare magic item while the artificer is attuned to the Wondermaker’s Key.

Vigilant. When the Wondermaker’s Key becomes vigilant, it gains the following properties:

While holding the key you can use an action to cast one of the following spells from it: Arcane Lock, Knock ,Tiny Servant, or Summon Construct. Once a spell has been cast using the key in this way it can’t be cast again until the next dawn.
As a bonus action, you can have a construct that is hostile to you within 20 feet make a saving throw against your spellcasting modifier. On a save the construct suffers no effects. On a failure, the construct is paralyzed. Once this property has been used it can’t be used until the next dawn.

Majestic. When the Wondermakers Key becomes majestic, it gains the following properties.

While holding the key and turning a specific way you can use a bonus action to open a doorway portal to a specific demi-plane called The Wondermaker’s Workshop and stay in it with up to 8 companions for 24 hrs. The Wondermaker’s Workshop uses the same spell information as Mordenkainen’s Magnificent Mansion. Additionally, magic items or objects crafted in the Wondermaker’s Workshop take half the crafting time. Once the key is used to access the workshop it can’t be accessed until the next dawn

As an action you can transform The Wondermaker’s Key into a Shield Guardian construct for 1 hour. The shield guardian listens to your commands and if it engages in combat its initiative is immediately after yours. Once the key has been used in this way it can’t be used again until the next dawn.