Bow of The Elements (5e Equipment)

Weapon (longbow), very rare (requires attunement)

When knocking and firing and arrow the user names an elemental damage type, the arrow then does that type of damage instead of piercing damage. Arrows fired through this bow deal 1d6 additional elemental damage of the same type as the arrow.
As an action, the user may fire an overloaded arrow from the bow that will explode on impact. All creatures in a 20-foot radius from where the arrow landed must succeed a DC 16 Dexterity saving throw to take half of the 6d6 elemental damage. The bow may use this effect twice, and regains all uses of this ability at dawn.
As a bonus action, you may command the bow to give you resistance to one type of elemental damage until the start of your next turn. For purposes of the bow, elemental damage types are: fire, cold, acid, lightning, thunder, and poison.