The conflict between the Uchiha and Senju clans has been ongoing since ancient times in Naruto series. From the time of Hashirama and Madara’s childhood, both clans have been in conflict till they became leaders of their respective clans. Their rivalry has been known to be fierce, but not only between Hashirama and Madara, even their younger siblings, Tobirama and Izuna, had their very own rivalry in this epic tale.
The Uchiha and Senju clans have been fighting since long before the era of ninja villages. The siblings continued their long-standing rivalry right from their childhood. This led to years of hatred for each other between the two. The conflict between the Tobirama and Izuna worsened, just like the Hashirama and Madara rivalry.
Their rivalry took a darker turn as they grew older. By this time, both the Uchiha and Senju clans had become extremely powerful and the war between them was at its peak. Izuna had the Mangekyou during the battle, but Tobirama created the Hiraishin technique that could counter Sharingan. This technique allowed Tobirama to move at lightning-fast speed, faster than the Sharingan could see. During the Tobirama vs. Izuna battle, Tobirama used the Hiraishin technique and successfully wounded Izuna.
Madara and Izuna had to withdraw from the battle after Tobirama used Hiraishin technique to wound Izuna. According to Madara, the injury Izuna sustained was fatal and eventually led to his death. Before Izuna passed away, he gave his Mangekyou to his elder brother, Madara, hence allowing him to unlock the Eternal Mangekyou. Therefore, Tobirama killed Izuna, as both clans were at war during that time.
In conclusion, the rivalry between the Uchiha and Senju clans is one of the critical conflicts in Naruto. In the Tobirama vs. Izuna showdown, Tobirama managed to use his Hiraishin technique and wound Izuna, leading to his eventual death. The rivalry between the Uchiha and Senju clans has become a significant part of the Naruto story.