Weapon Spirit

False Appearance. While the spirit is possessing a weapon with its Possess Weapon ability and is not moving, it is indistinguishable from a normal weapon of the type it is possessing.

Weapon Possession.  While the spirit possesses a weapon using its Possess Weapon ability, the following occurs:

• The spirit gains 10 temporary hitpoints.  If these hitpoints are reduced to 0, the posession ends, the weapon is destroyed, and the spirit reverts to its normal form.
• The spirit gains immunity to psychic and poison damage, and resistance to all other forms of damage
• The damage die(dice) and range of the spirits attacks changes to match that of the weapon it is possessing.  It cannot use ranged attacks while possessing a melee weapon and vice versa.
• The spirits AC changes to 11 (while possessing whips, slings, and similar weapons), 15 (while possessing clubs, staves, spears, javelins, and similar wooden weapons), 19 (while possessing swords, hammers, axes, and similar metal weapons), or 23 (while possessing adamantine weapons)
• the spirit can end its possession of a weapon as a bonus action on its turn.  The weapon falls to the ground in the spirits space and the spirit loses any remaining temporary hitpoints it has.

Multiattack.  The spirit makes 2 melee or 2 ranged attacks.  It can substitute one of those attacks with its Possess Weapon action.

Melee. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 3 (1d4 + 1) slashing damage.

Ranged.  Ranged Weapon Attack:  +5 to hit, range 20/60 ft., one target.  Hit: 4 (1d4 + 2) piercing damage.  If this attack is made while the spirit is possessing a weapon with the ammunition property, this attack ignores that property.

Possess Weapon.  The spirit targets one non-magical weapon it can see within 30 feet of itself.  If the weapon is not being wielded or held, it flies to the spirit's location and is possessed by the spirit.  If the weapon is being wielded or held by a creature, that creature must succeed on a DC 13 Strength Saving Throw, retaining their grip on the weapon on a success and causing the possession to fail.