Partial Undead

For one reason or the other, you have died and been resurrected. Maybe you died unjustly, and moments after your heart stopped, a patron took pity upon you and revived you. Maybe you were in the process of dying and were spared, but the process was interrupted before you could fully revive. Maybe you were once undead and were turned back into your mortal self. You're alive again...mostly. You're not quite mortal nor are you undead, you're in a void-like spot in between. You can die just as usual, but have some of the abilities of the undead.

Nerve of the Dead- You are resistant to necrotic damage,  poison, as well as fatigue and exhaustion effects.

Burdened by Light-You are vulnerable to radiant damage.

The Graveyard Shift- If a long rest is unable to be taken, you can instead take a short rest and have it equal to one long rest. This can only be used once per every 48 hours.

A Brush with Death-You are also susceptible to heart palpitations, small moments where your heart will briefly stop in your chest before starting once more as usual. These occur whenever your character interacts with something that would remind them of either a. a tragic instance from their past before dying b. the person/thing that originally killed them, or c. any stimuli associated with your death or resurrection (depending on whether or not your death or revival was more traumatic). Once a palpitation occurs (either at the DM's decision or if the player believes this would 'trigger' them), the player must make a CON saving throw (DC 15). If succeeded, your heart immediately begins beating and you can return to functioning as normal, if not a little shaken. If failed the first time, the player has disadvantage on skill checks for 10 minutes. If a second constitution save is made and failed before taking a short/long rest, the player becomes frightened for 10 minutes. If a third save is failed before taking a short/long rest, the player becomes stunned. On this, a reroll can be made either at the end of their turn, or after 5 minutes. If failed, a reroll can be made at the same intervals until succeeded, unless they are removed from the situation that was initially triggering them, then the effect wears off after the 5 minutes. The effects of the third roll will affect the player for every future failed save before taking a short or long rest.