At 2nd level, ghouls have a natural ability to regenerate. As a action, you can regain a number of hit points this uses a D6 dice however you become more hungrier making you more prone to lashing out and trying to kill and eat the nearest human

you have thicker skin making it your health go up ( +10 constitution )

At 3rd level, your able to manifest a deadly limb or limbs, granting you a magical natural weapon. You have the choice between Rinkaku, Koukaku, Bikaku, and the Ukaku. You are now always under the effect of the jump spell.

At 3rd level, your hardened skins provide defense against most types of trauma, granting you an Unarmored Defense of 10 + Constitution modifier + Dexterity modifier. You cannot use a shield to gain this effect.

At 5th level, you can choose to regain missing or damaged limbs or body parts during a short or long rest for 3 hit dice. These hit dice are not regained if they are spent during a long rest.

At 10th level, when you take the search action, you detect the location of any living or dead Humanoids within 30 ft. of you that produce a smell.

At 11th level, due to the power of your mutated RC Cells, you are considered to have the Powerful Build feature and are counted as one size larger when determining you ability to carry, push, pull or lift objects

At 14th level, whenever you take the attack action, you can attack a second time. If your Kagune has multiple attacks, then you can use all of them for each attack action (E.x if you have Rinkaku tails, and you have this feature, you can attack a number of time in one attack action equal to the number of Rinkaku tails you have, you can then do it again on your second attack action).