Magic Items

This is Commander Manta’s lucky charm. He never lost a battle so long as he had this on him.

Weapon (warhammer), legendary (requires attunement)
Matalotok, the Frost Father, is an ancient hammer fashioned by Thrym, the god of frost giants. The favored weapon of the demon lord Kostchtchie, Matalotok is frigid to the touch and wreathed in mist.
You are immune to cold damage while holding Matalotok. Whenever it deals damage to a creature, the hammer radiates a burst of intense cold in a 30-foot-radius sphere. Each creature in that area takes 10 (3d6) cold damage.

The hilt of this weapon is covered with carved, ancient Rellanic runes that seem to comprise nonsensical words or, possibly, a list of proper names.

You have truesight out to a range of 60 feet. This blessing is found in the Dungeon Masters Guide.

Weapon (longbow), very rare (requires attunement)
When you nock an arrow on this bow, it whispers in Elvish, "Swift defeat to my enemies." When you use this weapon to make a ranged attack, you can, as a command phrase, say, "Swift death to you who have wronged me." The target of your attack becomes your sworn enemy until it dies or until dawn seven days later. You can have only one such sworn enemy at a time. When your sworn enemy dies, you can choose a new one after the next dawn.
When you make a ranged attack roll with this weapon against your sworn enemy, you have advantage on the roll. In addition, your target gains no benefit from cover, other than total cover, and you suffer no disadvantage due to long range. If the attack hits, your sworn enemy takes an extra 3d6 piercing damage.
While your sworn enemy lives, you have disadvantage on attack rolls with all other weapons.

This elven bow has the soul of a Thayan rebel permanently