Naruto vs Amphibia
Connection:
Both are the deuteragonists with brooding and arrogant personalities who came from popular series of their respective media (Anime/Manga and Cartoons respectively). who serve as both rival and best friend to their series' main protagonists (Naruto Uzumaki and Anne Boonchuy respectively)
Both are skilled weapons and close combat as well as having mystical powers due to being connected with something (The Rinnegan and The Calamity Gems respectively)
Both went to school and were trained by someone who was highly skilled in martial arts (Orochimaru and Captain Grime respectively)
Both had hostility and a grudge against the main protagonists, even turning on their own allies and becoming an antagonist, but later redeemed themselves and rejoined the heroes
Both have a difficult relationship with their parents
Both have also joined a coalition force (Allied Shinobi Forces and The Toad Army/Wartwood Resistance respectively) against the main villain (Madara Uchiha and King Andrias /The Core respectively)
