GHOST KNIGHT

There exist knights and warriors who have a close connection to the realm of ghosts and spirits. Known as Ghost Knights, these fighters embrace the Ethereal Plane and its denizens to become spectral warriors, fearing neither death nor paint. Ghost Knights develop abilities to see and enter the Ethereal Plane, and eventually can become incorporeal themselves.

Return from the Grave,

to return from deadly attacks. When you are reduced to 0 hit points but not killed outright, you can drop to a number of hit points equal to half your fighter level rounded up (minimum of 2) You can't use this feature again until you finish a long rest

Spirit Sight

At 3rd level, you have sense for detecting the presence of spirits. As a bonus action, you can cause your eyes to become pale and emit ethereal smoke, allowing you to see up to 30 feet into the Ethereal Plane while you are on the Material Plane, and vice versa for up to 1 minute. You can use feature twice per short or long rest. Additionally, you gain proficiency in the Intimidation and Religion skills

PHANTOM LIFE

By 10th level your have become more spirit than mortal You are immune to disease, and you do not need to eat or breathe, but you can ingest food and drink if you wish

GHOST WALKING

At 10th level, you can move like a ghost. As a bonus action, you can cause your body to become partially incorporeal until the end of your turn, allowing you to move through other creatures and objects as if they were difficult terrain by temporarily making your body incorporeal. If you end your turn inside a creature or object, you are immediately shunted to the nearest unoccupied space that you can occupy and take force damage equal to your fighter level
You can use this feature a number of times equal to your Constitution modifier (minimum 1) per short or long rest.

SPECTRAL ATTUNEMENT

At 15th level, you have become more spirit than mortal You gain resistance to necrotic damage, and you become immune to the frightened condition

SPIRIT FORM

By 18th level you can become a ghost yourself. As a bonus action, you can transform yourself into a ghostly form. In this form, you have resistance to all damage except force and radiant damage, and you gain a fly speed equal to your movement speed
You remain in this form for 1 minute. It ends early if you are incapacitated if you die, or if you dismiss it as a bonus action.
Once you have used this ability, you can't do so again until you finish a short or long rest.