Konoha Hokage.
The First Hokage excelled at Wood Release.
The Second Hokage excelled at Water Release.
The Third Hokage excelled at...
Clearly being Hokage, not a single one of them primarily used Fire Release ninjutsu.
Second Hokage Tobirama Senju's Water Release was even more monstrous; even when facing Second Mizukage Gengetsu Hozuki, Tobirama Senju did not fall behind in Water Release. Coupled with his forbidden techniques, even if Gengetsu Hozuki appeared right before Tobirama Senju, he would more than likely be miserably defeated in disgust.
At this moment, Second Hokage Tobirama Senju was fully displaying his prowess in Water Release. He used Water Release to torture a group of Mist ninjas who specialized in Water Release until they doubted their lives.
The sacrifice used by Hiruzen Sarutobi to summon Tobirama Senju was merely a jonin, so his strength was not as terrifying as it had been during the Fourth Great Ninja War. The reason he was currently suppressing Yagura Karatachi and Mei Terumi was entirely because his ninjutsu and forbidden techniques were strong enough.
Furthermore, Tobirama Senju in the Impure World Reincarnation state possessed infinite chakra, allowing him to release ninjutsu to his heart's content without needing to worry about chakra consumption.
The infinite chakra of the Impure World Reincarnation was just like a mobile phone plugged into a charger, constantly recovering chakra at every moment.
Normal ninjas, when feeling chakra depletion, needed to extract chakra from their physical cells and spiritual energy, making it impossible for them to achieve infinite recovery.
This kind of infinite chakra referred to the recovery speed of chakra, not an infinite storage volume of chakra within the body.
The amount of stored chakra within the body of an Impure World Reincarnation ninja depended on the chakra volume the resurrected ninja had during their lifetime