Magic Items

Ring, rare (requires attunement) This ring stores spells cast into it, holding them until the attuned wearer uses them. The ring can store up to 5 levels worth of spells at a time. When found, it contains 1d6 - 1 levels of stored spells chosen by the DM. (2x Mirror Image) Any creature can cast a spell of 1st through 5th level into the ring by touching the ring as the spell is cast. The spell has no effect, other than to be stored in the ring. If the ring can't hold the spell, the spell is expended without effect. The level of the slot used to cast the spell determines how much space it uses. While wearing this ring, you can cast any spell stored in it. The spell uses the slot level, spell save DC, spell attack bonus, and spellcasting ability of the original caster, but is otherwise treated as if you cast the spell. The spell cast from the ring is no longer stored in it, freeing up space.

Wondrous item, rare (requires attunement)
While wearing these bracers, you gain a +2 bonus to AC if you are wearing no armor and using no shield.

Weapon (any bow), very rare (requires attunement)
This bow has multiple strings and resembles a lyre or small harp. By strumming the strings while setting an arrow to the bow, you imbue the arrow with magic.
You can play one of the following melodies when you use the bow to make a ranged weapon attack. You must choose to do so before you make the attack roll, and you can play only one melody per attack.
Melody of Precision. If you’re proficient in Performance, you gain a +1 bonus to the attack roll. If you have expertise in Performance, you gain a +2 bonus instead.
Melody of Reverberation. The melody you strum echoes loudly. On a hit, the target takes extra thunder damage equal to your Charisma modifier.
Guardian: The Bow whispers Warnings to it's Owner granting a +2 on Initiative Rolls

Source: Xanathar's Guide to Everything

Wondrous item, common
You can cut this 50-foot coil of hempen rope into any number of smaller pieces, and then use an action to speak a command word and cause the pieces to knit back together. The pieces must be in contact with each other and not otherwise in use. A rope of mending is forever shortened if a section of it is lost or destroyed.
Unusual Material: This "Rope" is a tentacle and it defies every logic known to mankind.

The intense psionic scream of a dying elder brain dragon left a psychic splinter in your brain. For the better or worse it grants you resistance against spells and magical effects. Now you have to just find a way how to deal with the voices in your head!

Wondrous Item, Common
While held up to your ear, this horn suppresses the effects of the deafened condition on you, allowing you to hear normally. This item is found in Xanathar's Guide to Everything, pg. 137.
Sentinel. This item glows faintly when aberrations are within 120 feet of it.
This is a typical earring that a githyanki warrior would wear when venturing out into the world. Because this item can be worn as an earring, it need not be held close to the ear to produce the intended effect.

Balagos’ Belt (+3 Dragonhide Belt)
Wondrous Item, Very Rare (Requires Attunement by a Monk)
This finely detailed belt is made of dragonhide. While wearing it, you gain a bonus to the saving throw DCs of your ki features.(+3) The bonus is determined by the belt’s rarity. In addition, you can use an action to regain ki points equal to a roll of your Martial Arts die. You can’t use this action again until the next dawn.
Harmonious. Attuning to this item takes only 1 minute.

Bahamut’s Blessing (Blessing of Magic Resistance)
You have advantage on saving throws against spells and other magical effects.

Heavy armor, legendary
You have a +3 bonus to AC while wearing this armor.
This item is found in the Dungeon Master’s Guide.
Song Craft. Whenever this item is struck or is used to strike a foe, its bearer hears a fragment of an ancient song.
This magnificent suit of plate armor was forged by the same legendary smith that crafted the Undisputed Multiversal Championship belt. As the champion marches forth, their presence is marked by the resounding clangor of steel and the shimmering brilliance of their armor—a shield against physical harm and a symbol of their indomitable spirit. In every clash and confrontation, the armor stands as a testament to the champion's honored status, destined to shape the fate of realms and etch their name in the annals of legend

Wondrous item, common (requires attunement by a spellcaster)
Etched with eldritch runes, this 1-inch-diameter ruby allows you to use a simple or martial weapon as a spellcasting focus for your spells. For this property to work, you must attach the ruby to the weapon by pressing the ruby against it for at least 10 minutes. Thereafter, the ruby can't be removed unless you detach it as an action or the weapon is destroyed. Not even an antimagic field causes it to fall off. The ruby does fall off the weapon if your attunement to the ruby ends.
This item is found in Xanathar’s Guide to Everything.
The Undisputed Multiversal Championship belt is made of polished gold and inlaid with decorative gems. The blood-red rubies inset into the belt can be removed only by the reigning Multiversal Champion. Once removed, they function as rubies of the war mage.