when you change forms you can pass through walls and your clothes and weapons change with you, as well as other items. you do psychic or necrotic (choose one to keep) damage with any weapons that have changed with you. you have a small glow to you in this form, and you are completely quiet, and do not affect physical items, when you talk, it sounds like an echo. you have advantage on stealth in this form unless the DM says otherwise. in this form you cannot be affected by physical attacks and you count as an undead creature. if an undead creature attacks you you take half damage, and if you are attacked with magic you take the full damage. If you someone uses a dispel or a similar spell you are immediately changed back into your physical form.

scince you had lived another life your experiences gives you advantages