Curse of eternity

Your inmortal soul is attached to this world:

• Your Constitution score is increased by 1.
• Your soul is attached to the armor, so you aren't wearing it in terms of class features (except if it applies to the AC). After a long rest, your hexaustion level is reset to 0, but you must make a Constitution saving throw (with adventage) (DC 15) or gain one hexaustion level.
• If your armor gains "Broken" status, your soul is released from it, dropping your AC to 10+DEX (or any unarmored AC improvement you have). You become invulnerable to physical damage (Bludgeoning, Piercing, Slashing) except it comes from magic sources. You also gains half of your player level as bonus hp. After 3 rounds, you and your remaining equipment vanish and get teleport to a safe area. Then your soul needs to be attached again to an armor to remind in the physical plane. While you are in this state, your able to cast spells and use bonus actions whenever they don't supose any physical interaction.