Preta Path

The grants the user the ability to absorb chakra in any form. Pain channelled the Preta Path through the corpse of a Kusagakure shinobi.

This ability is primarily defensive in nature as it is capable of absorbing chakra from an individual through physical contact. In addition to this, the Preta Path is able to absorb ninjutsu-based techniques that are pure chakra or chakra based, thereby nullifying their effect. It doesn't absorb physical attacks, like Gaara's sand, but does drain the sand's chakra. This goes the same for Earth Release techniques and Wood Release techniques. This is done by forming a barrier around the user's entire body, allowing them to absorb attacks from all directions.

Although the ability is able to absorb senjutsu chakra, the user is still vulnerable to the effects of turning into a stone statue from absorbing too much of it.

During the Fourth Shinobi World War, Nagato used the Preta Path to absorb Killer B's chakra while he was in his Version 2 form. He then apparently used the chakra to revitalise his body to its state before it was emaciated by the Demonic Statue of the Outer Path. It also restored his hair colour back from white to red, as well as the damage done to his legs. However, presumably due to loss of muscle memory, he was not able to use the legs completely.

Influences
In Buddhism, the Preta realm (also known as the Hungry Ghost realm) is a reincarnation based on strong possessiveness and desire which were cultivated in a previous life or lives. The Preta are humanoid creatures which are perpetually hungry and thirsty, but are unable to satisfy themselves, living lives similar to those of hopeless addicts trying to appease their unyielding hunger. In appearance, the Preta are deathly pale, emaciated figures, which contrasts with Pain's Preta Path's hefty stature. In Hinduism Preta could also mean ghosts this also relates to the technique the Preta path uses.