Ice Staff (5e Equipment)
From D&D Wiki
A stronger version of the lightning rod, this staff features 7 glowing gemstones, one large one and six smaller ones at the tip that act as an arcane focus. If a lightning or thunder spell is cast, the rod transforms to cast the spell in place of the wielder's hands, though you can still cast spells normally. When taking the attack action, you can:
Basic Melee Attack You swing the staff like a club. Make a melee attack. On a hit, you deal 1d4 bludgeoning damage + your Strength modifier + 1 lightning damage.
Ranged Spell Attack (costs 1 mp). You swing the rod, and a bolt of lightning from the tip up to a range of 90 feet, which on a hit deals 3d6 lightning damage. You add your Intelligence modifier to the attack and damage rolls of this attack.
Magic Melee Attack (costs 1 mp). With a blast of lightning, a long spear-head of lighting forms from the head of the largest gem. Now, when you make a melee attack, it now deals 1d6 lightning and 1d6 slashing damage. After 6 rounds of combat, it will disappear.