Magic Items

Staff of Power (Unbreakable)
Staff, weapon, very rare (requires attunement by a sorcerer, warlock, or wizard)
This staff has 20 charges and can be wielded as a magic Quarterstaff that grants a +2 bonus to attack rolls and damage rolls made with it. While holding it, you gain a +2 bonus to Armor Class, saving throws, and spell attack rolls.
Spells. While holding the staff , you can cast one of the spells on the following table from it, using your spell save DC. The table indicates how many charges you must expend to cast the spell.
Spell Charge Cost
Cone of Cold 5
Fireball (level 5 version) 5
Globe of Invulnerability 6
Hold Monster 5
Levitate 2
Lightning Bolt (level 5 version) 5
Magic Missile 1
Ray of Enfeeblement 1
Wall of Force 5

Regaining Charges. The staff regains 2d8 + 4 expended charges daily at dawn. If you expend the last charge, roll 1d20. On a 1, the staff retains its +2 bonus to attack rolls and damage rolls but loses all other properties. On a 20, the staff regains 1d8 + 2 charges.
Retributive Strike. You can take a Magic action to break the staff over your knee or against a solid surface. The staff is destroyed and releases its magic in an explosion that fills a 30-foot Emanation originating from itself. You have a 50 percent chance to instantly travel to a random plane of existence, avoiding the explosion. If you fail to avoid the effect, you take Force damage equal to 16 times the number of charges in the staff . Each other creature in the area makes a DC 17 Dexterity saving throw. On a failed save, a creature takes Force damage equal to 4 times the number of charges in the staff . On a successful save, a creature takes half as much damage.
Unbreakable. The item can't be broken. Special means must be used to destroy it.

Wondrous Item, Legendary (Requires Attunement by a Sorcerer, Warlock, or Wizard) This elegant garment is made from exquisite cloth and adorned with runes. You gain these benefits while wearing the robe. Armor. If you aren’t wearing armor, your base Armor Class is 15 plus your Dexterity modifier. Magic Resistance. You have Advantage on saving throws against spells and other magical effects. War Mage. Your spell save DC and spell attack bonus each increase by 2.

Wondrous Item, Legendary

This cube is 3 inches across and radiates palpable magical energy. The six sides of the cube are each keyed to a different plane of existence, one of which is the Material Plane. The other sides are linked to planes determined by the DM.

(1 Abyss, 2 Astral Plane, 3 Avernus, 4 Far Realm, 5 Material Plane, 6 Plane of Earth)

The cube has 3 charges and regains 1d3 expended charges daily at dawn. As a Magic action, you can expend 1 of the cube’s charges to cast one of the following spells using the cube.

Gate. Pressing one side of the cube, you cast Gate, opening a portal to the plane of existence keyed to that side.

Plane Shift. Pressing one side of the cube twice, you cast Plane Shift, transporting the targets to the plane of existence keyed to that side.

Legendary
"This Weapon seems to have some form of limited sentience, the wielder can feel the raging storm bound inside the metal. It is said the weapon itself was forged using a stolen part of Talos essence." War Leader, The bearer can use an action to cause his or her voice to carry clearly for up to 300 feet until the end of the bearer’s next turn. Weapon (Maul), Legendary (Requires Attunement) You gain a +1 bonus to attack rolls and damage rolls made with this magic weapon. The weapon has 5 charges. You can expend 1 charge and make a ranged attack with the weapon, hurling it as if it had the Thrown property with a normal range of 20 feet and a long range of 60 feet. If the attack hits, the weapon unleashes a thunderclap audible out to 300 feet. The target and every creature within 30 feet of it other than you must succeed on a DC 17 Constitution saving throw or have the Stunned condition until the end of your next turn. Immediately after hitting or missing, the weapon flies back to your hand. The weapon regains 1d4 + 1 expended charges daily at dawn. Giant’s Bane. While you are attuned to the weapon and wearing either a Belt of Giant Strength or Gauntlets of Ogre Power to which you are also attuned, you gain the following benefits: Giants’ Bane. When you roll a 20 on the d20 for an attack roll made with this weapon against a Giant, the creature must succeed on a DC 17 Constitution saving throw or die. Might of Giants. The Strength score bestowed by your Belt of Giant Strength or Gauntlets of Ogre Power increases by 4, to a maximum of 30.

Wondrous item, major tier, legendary (requires attunement by a wizard)

This thick leather-bound volume has a desiccated tongue pinned to the front cover. Five of these tomes exist, and it's unknown which one is the original. The grisly cover decoration on the first tome of the stilled tongue once belonged to a treacherous former servant of the lich-god Vecna, keeper of secrets. The tongues pinned to the covers of the four copies came from other spellcasters who crossed Vecna. The first few pages of each tome are filled with indecipherable scrawls. The remaining pages are blank and pristine.
If you can attune to this item, you can use it as a spellbook and an arcane focus. In addition, while holding the tome, you can use a bonus action to cast a spell you have written in this tome, without expending a spell slot or using any verbal or somatic components. Once used, this property of the tome can't be used again until the next dawn.
While attuned to the book, you can remove the tongue from the book's cover. If you do so, all spells written in the book are permanently erased.
This specific tome belongs to Szass Tam, leader of the Red Wizards of Thay. He watches anyone using this tome and can also write cryptic messages in the book. These messages appear at midnight and fade away after they are read.
This item can be found in the Dungeon Master's Guide.

Woe
Weapon (Longsword), Unique
This blade, formed from Father Llymic’s urge to destroy, is made from a bizarre, icy crystal that appears to bend and twist when viewed peripherally.
When Woe’s bearer is presented with an opportunity to act violently, Woe heightens its urge to do so.
You have a +3 bonus to attack and damage rolls made with this magic weapon.
If a character wields Woe while wearing Discord (plate armor from DDAL-DRW-15 Frozen Whispers), they are unharmed by temperatures as low as −60 degrees Fahrenheit.
Additionally, until the character removes Discord, they gain the flaw “Bright light enrages me.”