Baldur's Gate 3 - Most Rare and Hard to Find Items

Worgfang

Where:  Find the dagger in the Worg Pens at the Shattered Sanctum. It's inside a pile of bones in the pen with two worgs.

This dagger is the perfect weapon for fighting Goblins in Act 1, as it gives them disadvantage on attack rolls against the wielder.

Ring of Poison Resistence

Where: Locate the Shattered Sanctum and loot the skeleton before the Worg Pens, coordinates X340 Y15.

This ring grants Resistance to Poison damage and it can come in handy in sticky situations.

Smuggler's Ring

Where: Lead your party to the bank of the river, under The Risen Road, coordinates X: 58 Y:515. In a bush you will find a sceleton which drop the ring when looted.

As the name might suggest, this ring will help you build the perfect smuggler, adding +2 Stealth and +2 Sleight of Hand.

Staff of Arcane Blessing

Where: At the top of the Arcane Tower, on the working table, you will find a ring. Equipe it so it will reveal the hidden button in the elevator. Use it to reach the basment where you'll find the staff.

This staff grants its owner Bless Enchantment Spell as well as additional 1d4 to Saving Throws and Weapon Attack Rolls, as well as additional 2d4 to Spell Attack Rolls.

Amulet of Silanus

Where: Head to coordinates X: 263 Y: 480 near Druid Grove, close to the fishing bear. Move the rock out of the way and you'll be able to collect the amulet.

This amulet grants the Lesser Resrotation Level 2 Abjuration Spell.

Club of Hill Giant Strength

Where: Locate the Arcane Tower in the Underdark. Proceed with the exploring as you wish. Finally, you have to sit on a stool, which can be found at the top of the tower, and then break it.

This cub increses its owner's Strenght to 19. 

Spineshudder Amulet

Where: Head to Moonrise Towers, the room of Kethric Thorms, coordinates X: -169 Y: -198. The item won't drop unless you one-shot the chest containing the mimic in one hit.

When the wearer deals damage with Ranged Spell Attack, they inflict 2 Reverberation upon the target(s).

Killer's Sweetheart

Where: The ring can be found on the ground in the Gauntlet of Shar, by your mirror in the Self-Same Trial.

Upon killing a creature, your next Attack Roll will be a Critical Hit. It can be used once per Long Rest.

Band of the Mystic Scoundrel

Where: Lead your party to The Circus of the Last Days in Reithwin Town. Pickpocket Djinn Akabi's ring and win the rigged game. You'll be transported to a jungle. The ring is in a backpack, near the skeleton above the dinosaur cave, coordiantes  X:-1562, Y:-1518.

After hitting a creature with a weapon attack, the wearer can cast illusion or enchantment spells as bonus action.

Bonespike Gloves

Where: Kill and loot Strangler Luke during the event fight against the Farslayer of Bhaal Ghislev on the way to the temple of Bhaal. His body will disappear after the battle, so be quick.

This valuable item makes your attacks ignore Resistance to Slashing, Piercing, and Bludgeoning damage, which will help you in a lot of difficult fights.

Dark Displacement Gloves

Where: Go to The Circus of the Last Days in Reithwin Town, and talk to Popper. He's not marked as a merchant but he'll sell you these rare gloves and other goods.

These gloves grant +1 bonus to Attack Rolls when throwing, and may swap positions with the target if they fail a Dexterity Saving Throw. The character gains +1 Sleight of Hand as well.

Hellfire Engline Crossbow

Where: Use the Crafting table at Steel Watch Foundy. Combine Targeting Module ( coordinates X: -357 Y: -157 ), with a Steel Watcher Arm ( coordinates X: -280 Y: -165 ) and a  Watcher Crossbow Blueprint ( coordinates X: -330 Y: -157 ), all of them in the same building.

Not only does this crossbow cause significant damage, but it also grants you the Level 4 Lightning Arrow Transmutation Spell.