You gain +4 to dexterity while to get -1 to constitution.

You gain knowledge of your main language from your past life.

In spirit form you have a flying speed of 60 ft. You’re visible and can speak, however cannot interact with objects therefore cannot attack. Also, you become able to move through objects and creatures, but ending your turn in one of the two causes you to take 1d10 force damage. Being in this state causes you to be very vulnerable. You have vulnerability to every kind of damage due to being a spirit. Med kits, healing potions, or anything related has no effect on you as you’re a ghost. For this same reason you’re immune to being grappled, petrified, poisoned, and diseases. You can only be healed through magic, however being healed by Paladins and Clerics are null as it would be radiant.

You gain the ability to possess others. You must be above 50% of your max hit points to possess somebody. Possession takes a bonus action to do. To possess somebody, you need to be within 5 ft. Of them. The enemy you’re trying to possess must make a wisdom saving throw (DC 10 + wisdom modifier + proficiency bonus) On a fail they become possessed, and on a success they don’t. While in the body, you use their stat block. The only thing the enemy can do on their turn is redo the wisdom saving throw to attempt to free themselves. If the creature successfully kicks you out their body, you take damage equal to one of your hit dice. If you’re still in possession of an enemy when it dies, you leave the body, and are on 1 hit point. Leaving the body you currently possess takes an action to do. Doing so evokes opportunity attacks against you.

Special:

Undead have disadvantage against being possessed by you.

You can possess corpses, but this causes them to decompose quickly. You can only possess these for up to a hour.

If you possess a willing creature, they don’t have to make a wisdom saving throw; and you just start to possess them. Only when they no longer want you in their body do they start making wisdom saving throws.

Short or long resting with a physical body your wounds would heal overtime, and with being a war-forged you have your own fixing system. However, you have neither of these due to just being a spirit. To combat this, you’ve learned to heal yourself magically. After a short rest you gain one use of cure wounds, and after a long rest you gain two uses of cure wounds. You cast these with your dexterity modifier. The amount you heal increases when you level up. At 3rd 1d8+dex mod, at 7th level 4d8+dex mod, at 11th level 5d8+dex mod, at 15th level 7d8+dex mod, and at 18th level 9d8+dex mod.

You have no physical body meaning you can’t carry anything. Also you start with no starting equipment.