Echo (Kasumi)

Echo is the Yamabiko Clan's trademark Mijutsu (耳術, English TV: Hearing Jutsu, Literally meaning: Ear Techniques) Kekkei Genkai. It allows them to hear the world around through chakra so they can hear sounds a metaphysical level, which gives them access to various abilities that become famous.

Abilities
Echo is truly a Kekkei Genkai like no other. While some Kekkei Genkai's allow the user to see chakra, Echo is a Kekkei Genkai that is activated at birth to allow the user to hear the world around them through chakra. This is done not augmenting the user's hearing, but changing how they hear. Instead of picking up vibrations in the air the user's ears can detect the small vibrations that physical and mental energy makes when a sound is made. When the ears pick up the sound it processes to turn it into an "echo" or "soul" of the sound for their "mind's ear" to hear the world around them on the metaphysical plane. This grants the user a wide variety of abilities.

Firstly, the user is able to hear the chakra flowing through a person's Chakra Pathway System. This allows the user to easily determine a person's strength, their chakra signature, and what technique they are about to use.

The second ability is a complete immunity to harmful sounds. They have this because they no longer hear the world around them like most people do. They hear things not on the physical level, but the metaphysical level. The level where the frequency of all sounds are the exactly the same. On this level "loud" and "quiet" are concepts that don't exist.

The third ability is rooted on this difference between the physical sound and metaphysical side of sound. Users are able to hear everything around them, which allows them to paint a mental picture of what is around them with the sounds alone. In short, "seeing" through hearing.

The fourth ability comes from their ability to pick up the vibrations in mental energy. This allows them to hear sounds that only exist only on the metaphysical plane. Sounds like thoughts, emotions, soul words, voices of spirits in the Pure Land, the sound life makes when moving closer to death, and so on. Their ability to hear thoughts of course allows them to know what someone is thinking to always be a few steps head of them. This combined with the ability to hear emotions allows them to gain a perfect understanding of someone's mental state to predict their actions with nearly flawlessly. On the off chance an opponent becomes unpredictable they can use their ability to hear the voices of spirits to become clairvoyant by listening to their advice and warnings. This added to their ability to hear death approaching allows them to get a clear picture of the future provided it doesn't change.

The fifth ability of Echo is called Demonic Echo. Demonic Echo is only activated after a few years of using Echo. This is because it requires that the user's "mind's ear" is accustomed to hearing through chakra.