Arbiter

The blade of this weapon is decorated with strange symbols that dully hum with positive energy. While this magic weapon is on your person, you are immune to effects that turn undead.

Oaths to the Dead. While holding the glaive, you can use an action to cast Speak with Dead without expending a spell slot. When casting the spell using this feature or when interacting with a non-hostile undead creature that has the Incorporeal Movement trait, you may offer to take an oath to complete any unfinished business that the creature had in life. If the creature accepts, the creature (or its soul) becomes absorbed into the blade where it will remain until the oath is fulfilled or it leaves because the oath was not honored. While there, it can communicate with you telepathically and you share your senses and immunities with the creature so long as you are attuned to the weapon. You may also enable the creature to temporarily possess you for as long as you allow it to do so. You may make oaths equivalent to your Charisma modifier (minimum of 1). Creatures within the blade may freely communicate with each other if they mutually desire to do so. If oaths conflict with each other in anyway (even with those previously completed), you must forfeit one of the oaths taken. Depending on the nature of the oath you may gain one of the following additional features (your GM may alter or create additional oaths as needed):

• Oath to the Slain. You make an oath to avenge someone who was murdered. You gain have advantage on any attacks made against the targeted creature(s) and have advantage on any Intelligence or Wisdom checks made regarding them. This oath may also be completed upon observing the remains or resting place of the targeted creature if they have passed on. For every identified target beyond the 1st, add an additional charge to the total charges earned once the oath is completed.
• Oath to the Lost. You make an oath to bring someone back to a place or person of significance from their life so that they may come to rest or communicate a final message. Whenever acting in a way that intentionally moves you closer to fulfilling this oath, you gain advantage on any skill checks or saving throws. This oath may also be completed upon observing the remains or resting place of the targeted creature if they have passed on. For every identified target beyond the 1st, add an additional charge to the total charges earned once the oath is completed.
• Oath to the Regretful. You make an oath to fulfill an obligation or desire that someone had in their life. Whenever acting in a way that intentionally moves you closer to fulfilling this oath, you cannot make rolls at disadvantage and rolls made against you cannot be made at advantage. For every subsequent obligation or desire fulfilled beyond the 1st, add an additional charge to the total charges earned once the oath is completed.

Gifts of the Departed. If an oath is completed, the name of the individual you made the oath to becomes singed into the haft of the weapon and grants the weapon 1d4 charges. At 10 charges, you have advantage on charisma checks towards undead creatures. At 20 charges, you gain advantage on saving throws from undead creatures. At 30 charges, this weapon grants you resistance against necrotic and radiant damage (At 100 charges, it instead grants immunity). At 40 charges, you gain the ability to cast Spirit Shroud or Summon Undead (Ghostly Only; DC 10+ your proficiency bonus) at Xth level where X equals total charges divided by 10 (to a maximum of 9th level) once per day (no concentration required). If you have a minimum of 40 charges, you may expend charges to cast either of these spells at a level equivalent to the charges expended. If an oath is unable to be completed or is forfeited, subtract 2d4 charges. This weapon may contain 100 total charges.

Proficiency with a Glaive allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Heavy, Reach, Two-Handed, Graze