Kagune

A Kagune (赫子, shining child) is a ghoul's predatory organ and functions as their weapon and claws. It is usually as red as blood and flexible like the flow of water, but firm and sturdy. When released, a ghoul's physique is strengthened, they are more resilient and their mobility heightens. A kagune is composed of Rc cells, which flow just like blood, can become as solid as teeth and can be described as "liquid muscles". The Rc cells are released from a kakuhou piercing the skin, and the released Rc cells form the kagune. A kagune can be repeatedly hardened and softened at will by the ghoul.

Ukaku
An Ukaku kagune (Japanese 羽赫, romanization ukaku, English approximately shining feather) is spread out like feathers and is released from the shoulder area, it specializes in high speed attacks, most of the users seeming to have hugely enhanced speed. The kagune is lightweight and can be used to deliver high-speed attacks against an adversary, the primary method of attack is crystallising their kagune to deliver a high speed torrent of spike like projectiles, however whilst crystallised they are much stiffer and can't be used for short range combat. The kagune is suited both for short-distance and long-distance attacks, being able to use their kagune as a shield or as a way to enhance their strikes. Altogether, ukaku-type ghouls have a high chance to end the battle after a short time. However, releasing the Rc cells extremely decreases stamina. Thus, ukaku-type users lack endurance and are at a disadvantage if the battle drags on for a long time.

 Koukaku 

A Koukaku kagune (Japanese 甲赫, romanization kōkaku, English approximately shining shell) is metallic and released below the shoulder blade. This is achieved by a high density of Rc cells. It is heavy and extremely robust. Of all the kagunes, they have the greatest sturdiness and are especially suited for defense. Normally, they are generally shaped into armors or shields. But on the offense, they can be shaped like melee weapons such as drills, hammers or blades. Due to its high weight, a koukaku's speed is inferior to all other kagunes and the kagune is hard to wield.

 Rinkaku 

A Rinkaku kagune (Japanese 鱗赫, romanization rinkaku, English approximately shining scales) has an appearance similar to scaled tentacles and is released at the back around the waist. A rinkaku wielder has powerful regenerative abilities and its peculiar appearance and structure yield a superior striking power. A rinkaku excels in brute strength. This type's regenerative power is a result of the Rc cells easily binding together. Their Rc cells are more similar to liquids. However, this means that the binding force among the Rc cells must be weak, therefore making the kagune very easy to break.

 Bikaku 

A Bikaku kagune (Japanese 尾赫, romanization bikaku, English approximately shining tail) typically has a tail-like appearance and is released around the tail-bone/coccyx. It is good for medium-distance attacks and has decent offense, defense and speed. Thus, they have no notable strengths or weaknesses like the kagune based on other Rc types, meaning the kagune itself is treated as a surprise "trump card." A bikaku has better speed and durability against the brute-force, breakable rinkaku, allowing them to cut off the rinkaku's kagune. However, a bikaku will be overwhelmed by the faster ukaku user and will lose against the ukaku's long-range attacks.