Oath of Truth

Paladins who undertake the Oath of Truth are bound to strict tenets which task them to reveal deceptions and speak the truth, no matter how harsh it may be. Practitioners of this oath are expected to uphold a strict standard of honesty, and to encourage others to follow them. For those deities who invoke this oath, deception is the root of many evils, and those who cannot be swayed by words and example must be coerced through force.
    Often called “law bringers” or “brass knights,” paladins of the Oath of Truth have reputations for being strict and authoritative, but the most respected among them are known to be judicious and merciful. Some of these paladins seek only to correct deceptive behavior and punish those who exploit others through lies. Others, however, hold people to unbearably high standards, and may be seen as tyrants in the worst cases. Arvastus is a particularly strict deity, as he despises lies in every form. Paladins who swear themselves to him are called the Sunsworn, and often uphold his brutal will with force.
    The Oath of Truth can be sworn to other gods of justice, including Tyr, Helm, the Silver Flame, and Forseti. In the realm of Kaldaran, this oath may be sworn to such gods as Arvastus, Auron, Hemsir, and Juvalia.

Oath Spells
You gain oath spells at the paladin levels listed.

Oath of Truth Spells
Paladin Level    Spells
3rd                      command, detect magic
5th                      detect thoughts, zone of truth
9th                      dispel magic, spirit guardians
13th                    arcane eye, guardian of faith
17th                    dominate person, scrying

Channel Divinity

When you take this oath at 3rd level, you gain the following two Channel Divinity options.

Banish the Shadows. As an action, you raise your holy symbol and evoke a flash of divine light, dispelling illusions and revealing hidden objects and creatures. Choose any number of creatures you are aware of to NOT be affected by this feature. All other creatures within 30 feet of you must make a Constitution saving throw against your spell save DC, taking radiant damage equal to 1d10 + your paladin level on a failure and half damage on a success. A creature that cannot see or is blinded takes no damage from this feature.
    Regardless of whether a creature succeeds or fails, it is marked by a faint glow which produces dim light 5 feet from itself, and it does not benefit from any features to help it hide or perform Stealth checks. In addition, affected creatures cannot benefit from the invisible condition, and any illusions dissipate from the creature. Shapechangers retain their forms, but their true forms are faintly visible while marked.
    The mark remains on a creature for 1 minute. Illusions within range of this feature are also dispelled for the same duration. The effect ends early if you choose to end it (no action required), or if the creature is affected by the dispel magic spell or similar magic.

Eyes of the Witness. As an action, you bless yourself with divine insight for 1 hour. For the duration, you gain a +5 bonus to Insight and Perception checks.

Aura of Insight

Starting at 7th level, you and friendly creatures within 10 feet of you gain a bonus to Wisdom (Insight) and Wisdom (Perception) checks, as well as their passive Perception scores, equal to your Charisma modifier.
    At 18th level, the range of this aura increases to 30 feet.

Punishment

Also starting at 7th level, you can rebuke foes who attack you from afar or while unseen. Whenever you are targeted by an attack or spell effect from a hostile creature, you can use your reaction to learn its immediate location and move up to your movement speed in the most direct path towards that creature, without provoking attacks of opportunity. If you would enter a space within melee range of that creature, you can also make a melee weapon attack against the creature. This attack ignores any penalties from being unable to perceive the creature, and ignores half cover and three-quarters cover. After you make your attack, you no longer know its immediate location through this feature.
    Once you use this feature, you can’t use it again until you finish a short or long rest.

Unwavering Will

Beginning at 15th level, your soul becomes incorruptible to manipulative forces. You are immune to the charmed condition, and cannot be possessed.
    In addition, you can use Lay on Hands to end the charmed, frightened, paralyzed, and stunned conditions on yourself or another creature by spending 5 points from your pool.

Paragon of Truth

When you reach 20th level, you become an ideal champion of honesty and truth in the eyes of your patron deity. You know when a creature is lying and when it is omitting information, unless that creature is under the effects of the glibness spell or similarly powerful magic.
    Additionally, as an action, you can take on a fearsome, divine form. Radiant armor forms around you, your eyes glow a single, bright shade, and holy light radiates from your body. For 1 minute, you gain the following benefits.

- You have truesight out to 120 feet.
- Bright light shines from you in a 30-foot radius, and dim light shines out 30 feet further. Creatures within the bright light do not gain benefits from being invisible, and are not obscured by illusions. You also have advantage on attacks against creatures in bright light produced by this feature.
- If a hostile creature enters a space within 10 feet of you for the first time after you use this feature, it must make a Wisdom saving throw against your spell save DC. On a failure, the creature cannot attack any other creatures except for you until the end of its next turn, and it does not have advantage on attacks against you unless you are incapacitated.

Once you use this feature, you can’t use it again until you finish a long rest.