Einherjar

an Einherjar is an immortal warrior.  On some other material plane they died valiantly in combat.  Their heroism was so great, that they were brought back in this plane by their gods to be immortal warriors dedicated to combat.  While you are difficult to kill, you are still expected to rely on your own strength cunning and wit.  You are one who respect the cycle of Life and Death, though you are now outside of it.  You are not undead, though as you will never truly die.

Immortal Constitution

Beginning when you choose this archetype at 3rd level,You have advantage on all death saving throws and on constitution throws against being poisoned.

Valkerie's Blessing

Starting at 7th level, you can use the help action on your reaction to give an ally advantage on a strength, constitution, or death saving throw if they are within 60 feet of you.  If you do so, on your next reaction you may not take the attack action (this include any damaging spells).

Lonely Warrior

When you choose this class at 3rd level, you can no longer die. 

if you should fall while in combat WITH a weapon in your hands, your body and your possessions will fade away, and you will reappear 1 d4 days later in the last place you took a long rest. 

If you should fall out side of combat OR without a weapon in your hands your body will fade away leaving behind your possessions, and you will reappear without them 1 d8 days later in the last place you took a long rest.

Blessing of Tyr

At 10th level, If you did not attack the previous round, you may add 1 d4 of radiant damage to each of your attacks this round.  You cannot gain this benefit on the first round of combat after initiative or during surprise rounds

Archery

You gain a +2 bonus to attack rolls you make with ranged weapons.

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 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.

Two-Weapon Fighting

When you engage in two-weapon fighting, you can add your ability modifier to the damage of the second attack.

Blessing of Baldr

Starting at 15th level, If you are within 5 feet of an enemy, as your action you may impose disadvantage on them to hit any target other than you.  if you take damage, all slashing, piercing, and bludgeoning damage is halved.

Blessing of Asguard

At 18th level, you are the chosen one of your gods. Any time you come back from death saving throws (with the exception of Lonely Warrior) you are restored to half your maximum hit points and are resistant to all damage for 1 round.