D&D 5th: Demon Tower of Madness
Magic Item Attunement
Some magic items require a character to attune to them before the magical properties of those items can be enjoyed.
Attuning to a Magic Item: Attuning to a magic item requires that you first discover whether you can attune yourself to it. The identify spell is the most common way of discovering this fact. Unusual items magically reveal that fact to certain types of creatures or in certain circumstances.
The attunement process requires you to grasp or wear the item and spend 10 minutes concentrating on it. Depending on the nature of the item, this concentration can take the form of prayers, weapon practice, or meditation. In any case, the concentration period must be uninterrupted.
When you are attuned to an item, you can use any magical properties that require attunement. You also learn how to activate those abilities and any necessary command words or phrases to do so. See “ Using a Magic Item” for different methods of magic item activation.
An item can be attuned to only one creature at a time. A magic item might require you to meet one or more prerequisites before you can become attuned to it.
Maximum Number of Attuned Items: A creature can be attuned to no more than three magic items at any given time.
Ending a Magic Item’s Attunement: Your attunement to an item ends when you no longer satisfy the item’s attunement prerequisites, when the item has been more than 100 feet away from you for 24 hours, and when you die. You can also voluntarily end your attunement to an item with 10 minutes of uninterrupted concentration.
Here are two rules you can experiment with in your campaign.
Maximum Number of Attuned Items. A creature can have a number of magic items attuned to it at any time equal to its Charisma modifier (minimum 1).
Test of Wills. An intelligent or cursed magic item might resist any attempt to remove it, let go of it, attune to it, or end its attunement. Any such conflict is resolved as a Charisma contest between the magic item and its user. If the user fails to win the contest, he or she is forbidden from taking the specified action; however, another attempt can be made after 24 hours have elapsed. If the intelligent or cursed item does not have a specified Charisma score, assume it has Charisma 10 and a +0 modifier to its Charisma checks.
When attuned to you, some cursed items can terminate your attunement to other items. See the item’s description for details.