Obviously, Tony is one of the main characters. As for the villains, it could be a variety of well - known baddies from the original story universe.
One likely villain could be Loki. He's always up to no good and loves to play mind games, so a card game would be right up his alley. He might be the one who lures Tony into the game.
In the 'Tony joins villains card game' fanfiction, Tony's presence could completely change the dynamic of the game. Since he is a character with his own moral code, he might try to reform some of the villains through the card game. For example, he could use the game as a platform to teach them about fairness and cooperation. This would create an interesting conflict as the villains are not used to such concepts. Also, his skills and intelligence would likely give him an edge in the game, but the villains may try to undercut him using their underhanded methods. It could be a really exciting story with lots of twists and turns as Tony navigates this new and dangerous world of the villains' card game.
In this fanfiction, it could be that Tony has a hidden agenda when he joins the villains' card game. He might be trying to infiltrate the villains' group from the inside. So he plays along with their card game, making alliances and enemies within the group as he goes. All the while, he's secretly gathering information to take them down.
I don't know as I haven't read the novel. But probably some powerful and devious villains would be the main characters.
There are often heroes that serve as main characters in Ascension Card Game Story. These heroes have unique abilities that can help players gain an edge in the game.
I'm not sure as I don't know the specific Strip Card Game Story. But they could be a group of college students who are just looking for some wild fun.
Blake Belladonna is a favored character as well. Her stealth and mystery can add an exciting element to the card game fanfiction. Maybe she uses her ability to blend in and observe to figure out her opponents' card - playing habits and then uses that knowledge to win crucial battles.
I don't know the 'at tony's horror game story' well enough to say who the main characters are.
Caius is another important character in such fanfictions. He is usually portrayed as quite strict and unforgiving, and his reactions to Bella joining the Volturi can range from suspicion to begrudging acceptance. Also, Jane, with her special ability, has interactions with Bella that can be both menacing and oddly fascinating.
Obviously, Percy is one of the main characters. There might also be the leaders of the hunt, whoever they are in the fanfiction's setting. Maybe there's an experienced hunter who acts as a mentor to Percy during the hunt.