Five units of chakra were clearly not Hyuga Kagami's limit.
The curve of his lips rose further as his thoughts wandered. "Naruto has half of the Nine-Tails. Minato, sealed inside the Reaper's stomach, has the other half. Add the One-Tail within Gaara, the Three-Tails within Karatachi Yagura, and the Seven-Tails within Fū, and I have a full four Tailed Beasts at my disposal."
Hyuga Kagami could easily draw upon the Tailed Beast chakra of the three Jinchuriki: Naruto, Gaara, and Karatachi Yagura.
Although Fū was Takigakure's Jinchuriki, Takigakure simply could not protect her, so she spent most of her time in Konoha. With a few methods, it would not be difficult for Hyuga Kagami, the Fifth Hokage, to extract the Seven-Tails' chakra from her.
The only real trouble was the half of the Nine-Tails within Minato.
Minato had died after using the Reaper Death Seal, so his soul was inside the Reaper's stomach. Even a forbidden technique like the Impure World Reincarnation could not revive him.
Therefore, the only way to take the other half of the Nine-Tails from Minato was to follow the method Orochimaru had used in the original timeline: first use the Uzumaki Clan's forbidden technique to undo the Reaper Death Seal, cut open the Reaper's stomach, release Minato's soul from the Reaper's body, and then use the Impure World Reincarnation to summon Minato from the underworld back to the Ninja World.
If he succeeded, Hyuga Kagami could gain at least three units of chakra.
The complete Nine-Tails far surpassed the other eight Tailed Beasts. Even the half within Naruto was stronger than the Eight-Tails, and significantly stronger than the other seven Tailed Beasts.
Thus, the complete Nine-Tails counted as one and a half units of chakra, while the One-Tail, Three-Tails, and Seven-Tails together counted as another