Knight of the Raven

Before evil descended on the land of Barovia, it was home to an order of virtuous champions, the Knights of the Raven. United under the symbol of the raven, the symbol of their god Andral, their quest was to fight evil wherever it appeared. They prospered for centuries before the appearance of Strahd in their land, but now they are extinct. 

This fighter subclass is inspired by the prestige class from Expedition to Castle Ravenloft from 3.5e. It includes elements from that prestige class and a few additions of my own.  

Call Celestial Corvid

The celestial harrier raven has the stats of a raven from the Monster Manual with the following changes. Add your proficiency bonus to the raven’s AC, attack rolls, and damage rolls, as well as to any saving throws and skills it is proficient in. Its Beak attack is radiant instead of piercing. Its hit point maximum equals four times your fighter level. It is immune to radiant damage as well as any sleep, fear, and illusion magic. As an action, you can summon it a number of times equal to your proficiency bonus per long rest.

The raven takes its turn on your initiative. On your turn, you can verbally command the raven where to move as free action. You can use your bonus action to command it to take the Attack, Dash, Disengage or Help. If you don't issue a command, the raven takes the Dodge action.

If you are incapacitated, the raven is dismissed. The raven never requires your command to use its reaction, such as when making an opportunity attack.

You also have special commands for your raven. Each time you gain a new subclass feature, you will gain a new command for your raven. At 3rd level, you can use your bonus action to command the raven can harry a creature.

Harry: Your raven occupies the target's space within 30ft of you. The target makes a wisdom saving throw. The DC for this save is 8 + Charisma modifier + proficiency bonus. On a failure, the next attack that targets only this target has advantage.

Smite Undead

Starting at 3rd level, when you hit a creature with a melee weapon attack, you can deal radiant damage to the target, in addition to the weapon’s damage. The target must be undead, if used on a target of any other type, the target takes no additional damage. The extra damage is 3d8 radiant damage. The damage increases by 1d8 at levels 7, 10, 15, and 18 for a maximum of 7d8. You can use this feature a number of times equal to your proficiency bonus per long rest.

Raven's Cunning

Beginning at 7th level, you can use a bonus action to command the raven to use the Baffle action on its turn.

Baffle: When your raven occupies a target's space, the target must make a wisdom saving throw. The DC for this save is 8 + Charisma modifier + proficiency bonus. On fail, the target can't take reactions until the beginning of its next turn.

Conversational Croaker

Starting at level 10, have the ability to speak with ravens, including raven familiars and your own raven harrier. If a raven has an Intelligence above 2, you can communicate
with it as you would with a low intelligence human, such as a baby, using a language you both share. If the raven has animal intelligence (INT 1 or 2), you can communicate with it if you
were using the speak with animals spell, though this ability does not have a duration.

You can also command your raven to Glow.

Glow: When your raven can cast the light cantrip with itself as the target as an action.

Swift Judgement

Starting at 15th level, when you command your raven to take the Attack action, the raven can make two attacks. You can now command it to use Falter as a bonus action.

Falter: When your raven occupies a target's space, the target must make a strength saving throw. The DC for this save is 8 + Charisma modifier + proficiency bonus.  On a failure, they are knocked prone as your raven tackles the target to the ground. 

Celestial Aura

At 18th level, you attain the pinnacle of celestial resonance. Once per day, you can cast the spell Holy Aura at no cost. This ability resets after a long rest.

You can now command your raven to Heal.

While you have Holy Aura active, your raven can use its action to heal one creature each turn within your aura for 1d10 + your fighter level.