Besides being skeletal, the curse has given you great strength with its powerful magic. Your bones are toughened and resilient to endure whatever tasks you were denied death to complete. Your Strength score increases by 1, and your Constitution score increases by 2.

Accursed are beings whom have been brought back in an undead state.  It varies on just how old they might be when they were reanimated, so it is entirely possible some might have been around for more than hundreds of years.

Accursed are shadows of former selves held together by dark power.  Those who were evil before give in to the curse's destructive nature, forging havoc upon those still living.  Those of good nature tend to remain neutral for the most part, using only their abilities against those who would look to stir up harm.

Your base walking speed is 30 feet.

You have superior vision in dark and dim conditions.  You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light.  You cannot discern color in darkness, only shades of grey.

Being raised by and fueled by necromantic magic your body is attuned to its energy and is able to resist harm from outside sources.

Accursed as undead receive healing from poison, such as potions of poison, spells with poison properties, etc.  The only exception are cantrips with poison (I.e. Poison Spray) are not able to heal you.  Also, Accursed do not receive healing like the living and can also receive damage from healing effects.

Healing from potions containing poison you will heal the same amount as if it were a normal potion of healing, potion of greater healing, and so forth.  Healing from poisonous spells you will receive half as healing from the damage rolled.

The Accursed have the unholy ability to leech the souls of the living. As an action you can target any creature in range that is not a construct. The target must make a constitution saving throw against your spellsave DC. On a failed save the target takes 2d6 necrotic damage, on a successful save the target takes half damage. After the damage is done choose another creature in range, or yourself, to gain hitpoints equal to the damage done (does not heal constructs).If you target yourself or another willing creature with the attack the target can choose to fail the saving throw. The damage increases to 3d6 at 6th level, 4d6 at 11th level, and 5d6 at 16th level.

Being undead, Accursed are unable to eat, drink, smell, breath, or taste, and the feeling of touch is significantly numbed.  While in ways this may seem beneficial, it depends upon the subject who is cursed.  The memory of once bring alive and excluded from those normal sensors could be hard on an individual.

Accursed also struggle with swimming in water without sinking, due to their loss of buoyancy.

You know how to speak common along with another language of your choosing.