Sword of Faunus Slaying

Weapon, rare, optional attunement

In the wars between Faunus and the lands of Humans and Elves, many cruel and terrible weapons were created. One of the more common items is the Sword of Faunus Slaying, which were given to many of the commanders in the war. The Faunus managed to destroy several of these swords, and public outcry eventually led to their being locked in armories and ignored.

Without attunement, the weapon merely acts as a simple +1 longsword. However, any Faunus which happens see it drawn will be instantly revolted, with all the negative social results as would happen with attunement.

With attunement, the sword becomes a +2 sword (+4 against Faunus) with the following exra abilities:

Detect Faunus (2 times / day)
The wielder concentrates and the location of any Faunus within 100 feet is revealed. The identities or types of Faunus are not revealed, simply the number and direction. The effect is blocked by a thin sheet or lead or gold, by 3 feet or more of stone or rock, or by 6 feet or more of wood or soil
Illuminate Faunus (2 times / day)
By spending an action, the wielder outlines any Faunus within 60 feet in a manner similar to Faerie Fire. The affected creatures may make a Dexterity saving throw against DC 15 to avoid the effect
Burn Faunus (3 times / day)
Upon striking a Faunus, the wielder may deal an extra 1d10 fire damage
Hatred (constant)
While the sword is attuned (it need not be in possession), the wielder feels a primal hatred toward Faunus. The wielder is at Disadvantage on any social interactions, skill checks, and the like when involving Faunus; this negative extends to any in the wielder's party if the wielder is within 15 feet of that person. All Faunus will instinctively recoil from the wielder and recognize the wielder as inimically opposed to all Faunus