Blade: Like most Demon Weapons, Soul can change a part of his body into his Weapon form; in his case, he can transform his entire arm into the blade of a scythe, or partially transform it from the elbow downwards to make it easier for fighting. The blade is shown to point in different directions when he trasforms his arm just below the elbow. When becoming a Death Scythe, Soul, rather like Spirit, can have his blade come out of his arm rather than having his entire arm transformed (unlike Spirit's blades, Soul's blade runs parallel to his arm and is longer and narrower). Despite having the ability to perform a partial transformation, Soul's use and threat to the enemy is greatly reduced in the absence of his partner, although he has displayed decent combat skill, shown in the first encounter with Free where he stabbed the werewolf and managed to knock one of his ice attacks away to protect Maka. In battle, he does exhibit rather strong will, proceeding to get up even after being injured several times, shown in his battle against Giriko. However, as stated by Kid, Soul's speed and slashing skills are of a low standard.
Anti-Demon Wavelength and Soul Perception Achieved Through Soul Resonance: Soul has been shown to take advantage of Maka's Soul Perception and Anti-Demon Wavelength during Soul Resonance. When resonating his soul with Maka's, he can sense souls as well as she can. As a musician, he senses souls by hearing their Wavelengths, instead of seeing them like Maka. When Resonating, he shares the Anti-Demon Wavelength from Maka, protecting himself from insanity.
Black Blood: Soul posseses the Black Room inside his mind, inhabited by Little Ogre, which is born when he is infected with the Black Blood. Once the Black Blood is activated, Soul can allow it to invade the blood stream of those performing Soul Resonance with him. The Black Blood gives Soul and his infected partner(s) immense strength, at the cost of Soul, and possibly his partner, plunging into madness. Soul only uses this strength as a last resort, although Little Ogre constantly tempts him, playing on his dismay of not being a powerful Weapon on his own. However, as Soul gains more control over the insanity, he becomes gradually able to only draw out the strength of the Black Blood, and not the madness that comes with it. This does seem to strain him after overuse, however, as he has not learned to fully control it yet. When he uses too much power, he accidentally activates the Black Blood, although he still has control over its madness.
Piano: Soul's talent as a pianist becomes very useful as the series progresses, as he develops the ability to manipulate Wavelengths by treating the Soul Wavelengths of people like music. One thing he can do with this ability is create a perfect Chain Resonance even under impossible conditions. Inside the Black Room in his soul, he plays a piano, creating soundwaves and a rhythm that all the Soul Wavelengths of the Resonating individuals can follow. His piano-playing thus creates an almost perfect Resonance, and the team under his control can attack with great strength and fluidity in their movements. The team members of his Resonance rely on him to maintain the Resonance. Soul can also control their speed and efficiency in combat. By increasing the tempo of the song, the team members gain speed in their attacks, and by striking certain chords, their attack strength increases. He can also do the inverse of this i.e. slow down a person. He can also spread his partner Maka's Anti-Demon Wavelength through his piano, sometimes through great distances (he needs a medium to send the soundwaves through for this to be possible, though). After becoming a Death Scythe, he gains the ability of spreading Wavelengths using Arachne's ability of using spider webs. This makes his piano more powerful and he no longer needs a medium as he provides one himself. By playing the opposite sounds of a person's Wavelength on his piano, he can disrupt and incapacitate an opponent. Although this ability is invaluable, Soul risks falling deeper and deeper into the insanity of the Black Blood if he plays too long, and thus limits his playing time. He also needs Maka's Soul Perception in order to sense everyone else's Soul Wavelengths, meaning he cannot use his ability alone.
