1. Zabuza: Zabuza, the first antagonist in Naruto encountered by Team Seven, is known as the "Demon of the Hidden Mist." He is ultimately redeemed by Naruto and sacrificially dies in an act of bravery. 

2. Kimimaro: Kimimaro, the leader of the Sound Five and follower of Orochimaru, is a formidable antagonist. Despite his young age and illness, he battles Gaara, Rock Lee, and Kimimaro until his body fails and he dies.

Fans consider him a tragic character with immense potential. 

3. Kisame: Kisame, known as the "Tailless Tailed Beast," is a powerful antagonist. Despite his unfavorable appearance and affiliation with Akatsuki, his tragic backstory and self-sacrifice to protect vital information garner respect and sympathy. 

4. Madara Uchiha: Madara Uchiha, the main antagonist during the Fourth Great Ninja War, aspires to achieve the Infinite Tsukuyomi.

His eventual defeat by Black Zetsu results in a tragic and humiliating death, eliciting sympathy from fans. 

5. Orochimaru: Orochimaru is a notorious villain known for his cruel experiments and disregard for lives. However, his pursuit of knowledge and belief in the power of science over blind faith in gods or destiny make him a complex and intriguing character.