Yahiko's personality was similar to Naruto's. His dream was to be a leader of his village, and he never gave up no matter what. When he was alive, Yahiko had a strong "eye for an eye" philosophy. He hated the way Amegakure was looked at by the rest of the world, and hated what it had become. He was defensive of the village, saying that it was his dream to stop the endless rain, which he compared to tears, and protect the nation's citizens. Yahiko wanted to become the ruler of the world so there wouldn't be any more wars. Many of these traits were adopted by Nagato after Yahiko's death.
Yahiko had the ability to use water-based techniques, although the only example of this shown in the series was Water Release: Wild Water Wave, in which he was able to shoot a jet of water from his mouth. The Deva Path also had the ability to control rain, presumably Nagato fulfilling Yahiko's desire of "stopping the endless tears". The fact that he was seen carrying a large sword in the flashbacks implied that he was skilled in kenjutsu. He also had good leadership skills, was respected by all the Akatsuki members of his time, and although he viewed Nagato as the bridge of peace, everyone else viewed him to be the person who would lead them to true peace.
As the Deva Path, he was regarded as Nagato's most powerful and cherished of the Six Paths. Its main abilities revolved around the manipulation of attractive and repulsive forces, allowing it to repel or attract objects or people. However, it could not perform these techniques in rapid succession, leaving it vulnerable for a short period of time after each use. This period of time between usages varied from five seconds to several minutes, depending upon the force of the repulsion or attraction that the Deva Path had used. When performing a large-scale attack, Nagato had to first sever his connections with the other Paths and then employ his chakra only to the Deva Path for the attack. However this is considerably risky as the other Pains are slow to recover and leaves the Deva Path vulnerable. The Deva Path's Chibaku Tensei allowed it to release a black orb of energy that could attract all surrounding matter to form a huge makeshift terrestrial body. The Deva Path's most infamous and one of his greatest feats was single-handedly wiping out Konohagakure with one powerful Shinra Tensei. In addition to gravity manipulation, Nagato was able to use a number of other miscellaneous techniques through the Deva Path, something none of the other bodies had been shown doing. He was able to use the Shapeshifting Technique through the Deva Path to make body doubles of others with human sacrifices. Other techniques used included astral projection, barriers to protect hideouts, and the ability to control rain, a possible throwback to Yahiko (who wanted to be able to stop the rain in Amegakure), which even allowed him to sense the chakra of everyone in Amegakure, making stealthy entrances by enemies impossible. In the anime, the Deva Path also shows more Water Release techniques, possibly homage to Yahiko's affinity in his childhood, such as Water Release: Exploding Water Colliding Wave and Water Release: Wild Water Wave. In addition, like most of the other Paths, it possessed considerable strength and speed, as seen with its fight with Jiraiya, Kakashi Hatake and Naruto Uzumaki.
As Pain's main body, the Deva Path was the primary body used for performing the Sealing Technique: Phantom Dragons Nine Consuming Seals, which Akatsuki used to seal the tailed beasts. The members would convene to forcibly extract the beast from its jinchūriki's body over a three day period, depending on the number of people assisting with the sealing, and would then store it in a giant statue. He was not the only one who could use this technique, however. Tobi and the remaining Akatsuki members have been shown to initiate the extraction without using the Deva Path while it was occupied with invading Konoha.