Well, when kabuto was using his re-animation jutsu as to revive all strong and fallen shinobi's, why didn't he revive "IZUNA UCHIHA". He was as strong as Madara uchiha, and they both could have made this war even more interesting

Well , He along with his brother Madara Uchiha were renowned as the clan's two strongest members. Izuna was noted to be equal to his elder brother, Madara, in every way. Both of them had exceptionally strong chakra, even for Uchiha members and trained daily to hone their skills.