At the start of the series, Tamamo merely seems like a powerful yōkai who manipulates and fights as a means for his own selfish desires. After fighting alongside Nūbē and class 5-3 and solving a number of youkai problems, he grew fonder and fonder of the human race, to the extent that he would use "Megido", his most powerful fire-based ability, in order to destroy Zekki, the younger brother of Nūbē's Oni no Te. Tamamo also found himself unable to take Hiroshi's skull even when the opportunity presented himself later on, having learned too much of the human heart. This is a problem for him, as without a suitable skull his mental and physical faculties would eventually erode, leaving him to die as only a shell of his former self.
Having existed and trained his spiritual powers for centuries, Tamamo has become adept in many spiritual powers and abilities that he holds even without perfecting his "transformation jutsu". He is a master of "illusion jutsu", able to manipulate anyone to see whatever he portrays as long as there is motion. (even to the extent of creating clones of himself off the display of video game screens) Offensively, he uses a "yōko foxfire jutsu", allowing him to create and control a powerful fire-based attack which he can increase in power and intensity to burn his opponents. He can also handle certain other spiritual abilities like Nube's such as assisting in controlling spiritual energy and even the "youshin jutsu". When not using spiritual power, his main weapon is a paw-like neck catcher, which primary function is the extraction of suitable skulls for his "transformation jutsu", but can also be broken apart to surround himself and an opponent within a barrier for more powerful attacks.
In the manga liner notes for Volume 2, the author stated that Tamamo was intended to be a direct descendant of the Nine-Tailed Kitsune who was notorious as Tamamo no Mae. However, the fox appeared later in the story and was less than fond of Tamamo, thus leaving the name to be most likely an allusion, perhaps out of respect.