1. Ranma Saotome
2. Harry Potter
3. Naruto Uzumaki
4. Shinji Ikari
5. Usagi Tsukino
6. Lina Inverse
7. Ichigo Kurosaki
If you're wondering why it's these specific characters, It's a reference to a fanfic series I follow where these seven are presented prominently.
Moving on, this is Manga Ranma, Book Harry, Manga Naruto, Original series Shinji, Anime Usagi, Composite Lina, and Manga Ichigo.
Naruto still has Kurama
Shinji has his Eva
Usagi is the one from the first anime's continuity, not Crystal
Lina is a composite of her Novel, Anime, and Manga incarnations
This will be done in a variety of scenarios
1. Bloodlusted
2. In-Character
3. Multiple Rounds, with the winner of each round being removed from the next round until only two remain
And as a bonus, they sit an talk