Respect Where It Is Due. Even amongst those foreign to you, there is skill and hard work. Respect those that have risen in position and in power due to their own virtues.

Suffer Not A Threat. If there is a threat to your homeland or your ability to protect it, destroy that threat immediately and utterly. No quarter shall be given.

Waste Not. Do not waste food or drink, for many go without. Do not waste a swing of your weapon, as your enemy may live to hurt others.

For The Homeland. All of your actions on the battlefield, and to a lesser extent in life, are for those that you defend. Your homeland must be protected and cherished.

Sanction Is Sacred. Always receive permission before taking or using something that isn't yours. Especially if that thing is of divine significance, such as a soul or relic.

The Oath of the Bone Knight binds the oath taker's soul to the defense of their homeland, and connects it to the realm of the dead so that they can be risen in order to defend the homeland long after they have perished. Sometimes called bone lords, death knights, or the living dead, these paladins are often looked upon with mistrust and sometimes open antagonism in lands that haven't heard of them. Stoically, they press onward. They work forever for their homeland, their every breath in service of its defense. These paladins often adorn their armor with skulls and similar death and undead motifs, adding to their aura of intimidation and reminding them of their eternal pledge.

Taste of the Undead

Whenever you cast a spell that allows you to obtain an ally whose type you can choose, you can choose for it to be an undead. For example, find familiar allows you to obtain an ally, whose type you can choose between celestial, fey, or fiend. If you choose for the ally to be an undead, then it has immunity to poison damage, and the exhaustion and poisoned conditions.

Channel Divinity

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

Bone March. You can use your channel divinity to temporarily take control of skeletons around you. As an action, you present your holy symbol and utter a brief prayer of command. All undead within 30 feet of you that can see you and hear your prayer must make a Wisdom saving throw against your spellcasting DC. On a failure, they must follow your orders for 1 minute. Everytime they take damage due to your orders, they can attempt the Wisdom saving throw again. The combined CR of the undead controlled by this ability cannot be higher than your paladin level.

Death Strike. As a bonus action, you can channel the dark energies that are yours to command into your weapon, draining it of all color and causing cold mist to surround it. If you use your Divine Smite ability with your weapon while it is in this condition, the damage of your Divine Smite is necrotic.

When you hit an enemy with the weapon the target must succeed on a Constitution saving throw or else suffer one level of exhaustion and additionally have its movement speed reduced by 10 feet and be unable to regain health until the beginning of your next turn. All levels of exhaustion gained by this effect will go away after a single long rest.

Your weapon remains in this condition until either a minute has passed or you have successfully hit a living target with the weapon a number of times equal to your Charisma modifier. If the weapon is not already magical, it becomes magical for the duration.

Karrnathi Undead

Starting at 7th level, when certain conditions are met you can raise a powerful undead servant. You must have obtained the permission of the creature to cast the spell on it's remains before it died or from the spirit of the creature. The creature's maximum CR is 1, but increases to 2 at paladin level 14, and 3 at paladin level 20.

If both of these conditions are met, you can animate the dead creature as a skeleton or zombie version of itself. It will retain most of it's abilities including its personality, but will also be completely loyal and obedient to you. It lacks the ability to improve itself, and any resources it expends will be recovered half as quickly as normal. For example, if it could only use a specific ability once per day normally, after using the ability it would have to wait two days before being able to use the ability again. Additionally if it has a multiattack option it looses it.

This special undead is called a Karranthi Undead. You can only have one Karranthi Undead connected to you at a time; if you create a new Karranthi Undead, then the one currently connected to you ceases to be animated. You can release your currently existing Karranthi Undead as part of a ritual that takes 8 hours. Doing so allows it to exist without being connected to you, but it is no longer bound to be loyal and obedient to you and can attack you or act against you if it desires.

Additionally, any undead created by you are immune to being turned or instantly being destroyed by such an effect if they are within 15 feet of you. At 18th level, this extends 30 feet.

Exoskeleton of Undeath

Once you've reached 15th level, you can focus the power of your Oath into yourself and create magical plate armor made of bone that is fused with your body. Doing so takes 10 minutes of concentration, but the armor can be dismissed by you as an action at which point it turns into ash and leaves you unharmed. You cannot wear this armor and wear other armor, aside from shields.

When you are wearing the armor you are immune to the petrified, poisoned, and stunned conditions. You also gain resistance to necrotic and poison damage, and gain advantage on Charisma (Intimidation) checks. The armor does not have any Strength requirements to wear, you are always proficient in it, and it does not impose disadvantage on Dexterity (Stealth) checks due to being part of your body. It's AC is equal to 10 + half of your Paladin level.