Paladins of Dust

Chelic saw the man the moment he stepped into the ruined temple.  The fellow was youngish. His reddish-brown hair was curly and his skin was flawless.  He wore rimless spectacles and a suit of gray scale armor.  A shortsword lay across his lap and the fellow was reading a small, green book. 
Chelic cleared his throat.  The armored man looked up from his book and smiled.
“Hello again, Chelic.”
The elf frowned. “I’m sorry. Have we met?”
“Not that you’d remember.  Come to have another go at stealing the bones of General Oramyr?”
Chelic’s frown deepened.  “What are you talking about? This is the first time I’ve been here.”
“No,” said the young man.  He put down his book and stood.  He was short for a knight. As he drew his sword and approached, he added, “You’ve said that the other times we’ve fought as well.”
“You’re quite mad, aren’t you?” remarked Chelic, drawing his own blade.
The young man simple smiled and waited as if he had all the time in the world.

Paladins of Dust serve Naroth, the God of History and Memory.  They are usually charged with protecting places of historic importance: the site of a crucial battle, the tomb of a great king, the ruins of a fallen city.  Sometimes they are dispatched to secure artefacts of historical significance, transporting them to the Narothic Archives beneath the Range of Faces.
Paladins of Dust seldom come from a martial background. More often they emerge from the ranks of academics and scholars, people with a deep love and appreciation for history.  They do not rely on Charisma, as other paladin types do, but on Wisdom.
Adventurers hate encountering Paladins of Dust. How do you defeat someone who you’ve probably fought before, but you don’t remember?  As if that wasn’t bad enough, a Paladin of Dust’s attacks actually cause their enemies to age. Even if they don’t reset the clock, even if an adventurer manages to best a Paladin of Dust, he’ll probably be years older by the time he gets away.  It’s really not worth the trouble and most adventurers will simply walk away from a fight with a Paladin of Dust, assuming they’ve already lost it in some other timeline.

Hit Points
Hit Dice: 1d10 per level
Hit Points at 1st Level: 10 + Con Modifier
Hit Points at Higher Levels: 1d10 (or 6) + your Con Modifier per level after 1st.

Proficiencies
Armor: All armor and shields
Weapons: Simple and martial weapons
Tools: None
Saving Throws: Wisdom, Constitution
Skills: Choose two from Athletics, Insight, Intimidation, Medicine, Persuasion and Religion.

Historical Expertise
At 1st level, Paladins of Dust gain proficiency in History.  Their proficiency bonus for all Intelligence (History) checks is double.

Sense of Time
Also, at 1st level, Paladins of Dust develop a perfect sense of time. They always know the exact date and time.

Fighting Style
Starting at 2nd level, Paladins of Dust chooses a fighting style as a specialty. You cannot take a Fighting Style more than once, even if you later get to choose again.

Defense - While you are wearing armor, you gain a +1 bonus to AC.

Dueling - When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.

Great Weapon Fighting - When you roll a 1 or a 2 on a damage die for an attack you make with a melee weapon that you are wielding with two hands, you can reroll the die and must use the new roll, even if the new roll is a 1 or a 2. The weapon must have the two-handed or versatile property for you to gain this benefit.

Protection - When a creature you can see attacks a target other than you that is within 5 feet of you, you can use your reaction to impose disadvantage on the attack roll.  You must be wielding a shield.

Temporal Smite
At 2nd level, when you hit a creature with a melee weapon attack, you deal additional damage. Add a 1d8 to the weapon’s normal damage. This damage counts as magical and manifests itself as time passing for the subject of the attack.  Your enemy ages years for every blow you land. Staring at 9th level, you add 2d8 to the weapon’s normal damage.
You can use this feature a number of times equal to your Wisdom modifier (minimum of once). When you have expended all these uses, you cannot regain this feature until you finish a short or long rest.

Divine Vitality
By 3rd level, the divine power flowing through you makes you immune to the effects of aging and you cannot be aged magically.  You can still die of old age, however.

Ability Score Improvement
When you reach the 4th level, and again at 8th, 12th, 16th and 19th level, you can choose to increase one ability score by 2, or to increase two ability scores by 1.  As usual, you cannot increase an ability score above 20 using this feature.

Extra Attack
At 5th level, you can attack twice, instead of once, whenever you take the Attack action on your turn. At 17th level, you can attack three times.

Eye of Experience
Starting at 6th level, using your wisdom and experience, you can study another creature outside combat and deduce certain information about its capabilities. The DM can tell you one of the following: the creature’s Strength, Dexterity or Constitution score; its Armor Class or its class levels (if any).

The Grace of Naroth
Beginning at 7th level, you cannot be charmed while you are awake.

Shield of Ages
When you reach 10th level, you become resistant to damage from spells.

Rewriting History
At 11th level, you can use a bonus action to reroll the die for an ability check or saving throw. You must use the new roll.  After you have used this feature, you cannot use it again until you have completed a long rest.

Living History
At 13th level, outside of combat, you can project your consciousness into the past a number of hours equal to your Paladin of Dust level.  You cannot be perceived in the past, you cannot change anything that has happened, and your psychic self cannot be damaged.  You cannot leave the area you currently occupy.
You can use this feat a number of times equal to your Wisdom modifier (minimum of once). After expending all uses, you do not regain it until you finish a long rest.

Hands of Time
Beginning at 14th level, you can use your action to end one spell on yourself or one willing creature that you touch.
You can use this feature a number of times equal to your Wisdom modifier (minimum of once). You regain expended uses when you finish a long rest.

Healing Time
Starting at 15th level, you can use an action to restore hit points equal to your paladin of dust level. After using this feature, you must complete a long rest before you can use it again.

Time Out
At 18th level, you can use an action to stop the flow of time for everyone but yourself.  No time passes for other creatures while you take 1d4 + 1 turns in a row, during which you can use actions and move as normal.
The effect ends if one of the actions you use during this period affects a creature other than you or an object being worn or carried by someone other than you.  In addition, the effect ends if you move more than 1000 feet from the location you cast it.
After using this feature, you must complete a long rest before you can use it again.

History’s Champion
Your devotion to your deity has been rewarded.  Not only do you stop aging, but you gain the power to reduce your enemies to dust.  You choose a target within 60 feet of you that you can see. Your target must make a Dexterity saving throw (DC is your Paladin of Dust level + your proficiency bonus).  If they fail the save your target is reduced to dust and cannot be resurrected.