However, some of the more powerful devils like Sirzechs Lucifer might also be very likely to win. His incredible power and combat experience would make him a tough opponent in any death battle fanfiction. He has shown the ability to take on multiple strong opponents at once and still come out on top.
Vali is also a likely winner in many scenarios. His Divine Dividing ability gives him an edge in combat, being able to halve his opponent's power and double his own. In a death battle, this could be a game - changer.
Issei is a likely candidate. His over - the - top perverted nature could be a target in bashing fanfiction. Some might write stories where his actions finally catch up with him and he has to face the consequences of constantly objectifying women.
Issei could be a likely hero in such fanfiction. Even though he has a devil side, his human side might make him conflicted about the actions of some devils. He could turn against the devils who are causing harm and use his powers to bash them in order to protect his friends and the school.
Naruto and Issei are very likely crossover characters. Naruto, with his strong will and powerful ninja skills, would be an interesting contrast to Issei, the perverted but also determined protagonist of Highschool DxD. Another likely pair could be Sasuke and Vali. Both are brooding, powerful characters with their own agendas. Sasuke's Sharingan abilities could have some really cool interactions with Vali's powers in the context of this fanfiction. And of course, Kakashi could be a great crossover with some of the more strategic characters in Highschool DxD, like Sona, as he is known for his intelligence and combat skills.
Tatsumi would be a strong contender. He has his Incursio armor which gives him enhanced strength, speed, and durability. His combat skills have been honed through many battles against the Empire. Also, he has a strong will, which is crucial in a Death Battle situation.
Issei is often a very important character. His growth and development, especially in a death and rebirth context, can drive the story forward. Rias too, as her relationship with Issei and her role in the supernatural world of Highschool DxD can be greatly affected by such themes.
Issei would be a likely ally. He's the main character in Highschool DxD and is always looking for ways to become stronger. Sasuke's combat skills and knowledge could be very appealing to Issei. Also, Rias Gremory could be an ally. As a powerful devil and the leader of her peerage, she would recognize Sasuke's potential and value his skills in battles against common enemies.
Akeno could be a central character as well. Her unique powers in 'Highschool DxD' could be further developed with the addition of 'Fate' and 'gamer' elements. For instance, she could gain new skills or abilities through the 'gamer' system and use them in 'Fate' - like battles, making her a key figure in the fanfiction.
In the 'naruto vs ichigo death battle reaction fanfiction', it's difficult to determine a clear winner. Naruto's ability to use chakra and his vast array of jutsu like the Rasengan and Shadow Clone Jutsu are formidable. However, Ichigo's strength, speed, and the unique powers of his Zanpakuto, not to mention his Hollow form, are also extremely powerful. The outcome would likely depend on the specific circumstances of the battle, such as the location, the characters' mental states, and any unexpected twists the author might throw in.
A plotline where the characters from High School DxD are pitted against characters from other similar anime in death battles. Say, Issei against Ichigo from Bleach. This would be exciting as it combines the unique powers and fighting styles of two different anime universes, and fans can speculate on who would win based on their abilities and growth throughout their respective series.
One likely opponent is Luke Castellan. Since they have a complex relationship in the original series, it would be a very emotional and intense battle in fanfiction. Luke has his own set of skills and powers, and his motives would make the battle even more interesting.